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How to use useImperativeHandle method in Playwright Internal
Best JavaScript code snippet using playwright-internal
data.js
Source:data.js 
1export const questions = [2 {3 question: 'ÐÑбеÑи ÑвеÑ',4 type: 'withImage',5 options: [6 {7 image: '/color/black.jpg',8 id: 0,9 points: {10 useState: 10,11 useReducer: 5,12 useCallback: 3,13 useImperativeHandle: 6,14 useEffect: 5,15 useRef: 7,16 useLayoutEffect: 317 }18 },19 {20 image: '/color/blue.jpg',21 id: 1,22 points: {23 useState: 4,24 useReducer: 10,25 useCallback: 3,26 useImperativeHandle: 5,27 useEffect: 4,28 useRef: 4,29 useLayoutEffect: 330 }31 },32 {33 image: '/color/gray.jpg',34 id: 2,35 points: {36 useState: 3,37 useReducer: 4,38 useCallback: 10,39 useImperativeHandle: 4,40 useEffect: 3,41 useRef: 5,42 useLayoutEffect: 443 }44 },45 {46 image: '/color/green.jpg',47 id: 3,48 points: {49 useState: 3,50 useReducer: 1,51 useCallback: 5,52 useImperativeHandle: 10,53 useEffect: 3,54 useRef: 5,55 useLayoutEffect: 156 }57 },58 {59 image: '/color/orange.jpg',60 id: 4,61 points: {62 useState: 1,63 useReducer: 8,64 useCallback: 3,65 useImperativeHandle: 5,66 useEffect: 10,67 useRef: 1,68 useLayoutEffect: 769 }70 },71 {72 image: '/color/pink.jpg',73 id: 5,74 points: {75 useState: 3,76 useReducer: 4,77 useCallback: 3,78 useImperativeHandle: 9,79 useEffect: 6,80 useRef: 10,81 useLayoutEffect: 482 }83 },84 {85 image: '/color/purple.jpg',86 id: 6,87 points: {88 useState: 1,89 useReducer: 6,90 useCallback: 5,91 useImperativeHandle: 2,92 useEffect: 5,93 useRef: 5,94 useLayoutEffect: 1095 }96 },97 {98 image: '/color/red.jpg',99 id: 7,100 points: {101 useState: 8,102 useReducer: 5,103 useCallback: 1,104 useImperativeHandle: 3,105 useEffect: 9,106 useRef: 8,107 useLayoutEffect: 7108 }109 },110 {111 image: '/color/yellow.jpg',112 id: 8,113 points: {114 useState: 3,115 useReducer: 9,116 useCallback: 5,117 useImperativeHandle: 3,118 useEffect: 1,119 useRef: 1,120 useLayoutEffect: 4121 }122 }123 ]124 },125 {126 question: 'ÐÑбеÑи ÑилÑм',127 type: 'withImage',128 options: [129 {130 image: '/movie/brother.png',131 text: '"ÐÑаÑ"',132 id: 0,133 points: {134 useState: 10,135 useReducer: 5,136 useCallback: 2,137 useImperativeHandle: 6,138 useEffect: 6,139 useRef: 7,140 useLayoutEffect: 3141 }142 },143 {144 image: '/movie/zhmurki.png',145 text: '"ÐмÑÑки"',146 id: 1,147 points: {148 useState: 4,149 useReducer: 10,150 useCallback: 5,151 useImperativeHandle: 5,152 useEffect: 4,153 useRef: 4,154 useLayoutEffect: 3155 }156 },157 {158 image: '/movie/indiana.png',159 text: '"Ðндиана ÐÐ¶Ð¾Ð½Ñ Ð¸ поÑледний кÑеÑÑовÑй поÑ
од"',160 id: 2,161 points: {162 useState: 5,163 useReducer: 4,164 useCallback: 10,165 useImperativeHandle: 4,166 useEffect: 3,167 useRef: 4,168 useLayoutEffect: 4169 }170 },171 {172 image: '/movie/godfather.png',173 text: '"ÐÑеÑÑнÑй оÑеÑ"',174 id: 3,175 points: {176 useState: 3,177 useReducer: 1,178 useCallback: 8,179 useImperativeHandle: 10,180 useEffect: 3,181 useRef: 6,182 useLayoutEffect: 1183 }184 },185 {186 image: '/movie/beauty.png',187 text: '"ÐÑаÑоÑка"',188 id: 4,189 points: {190 useState: 1,191 useReducer: 7,192 useCallback: 3,193 useImperativeHandle: 5,194 useEffect: 10,195 useRef: 8,196 useLayoutEffect: 7197 }198 },199 {200 image: '/movie/avengers.png',201 text: '"ÐÑÑиÑели: Ñинал"',202 id: 5,203 points: {204 useState: 3,205 useReducer: 4,206 useCallback: 7,207 useImperativeHandle: 9,208 useEffect: 6,209 useRef: 10,210 useLayoutEffect: 3211 }212 },213 {214 image: '/movie/revenant.png',215 text: '"ÐÑживÑий"',216 id: 6,217 points: {218 useState: 1,219 useReducer: 6,220 useCallback: 5,221 useImperativeHandle: 2,222 useEffect: 5,223 useRef: 5,224 useLayoutEffect: 10225 }226 },227 {228 image: '/movie/nocountry.png',229 text: '"СÑаÑикам здеÑÑ Ð½Ðµ меÑÑо"',230 id: 7,231 points: {232 useState: 8,233 useReducer: 5,234 useCallback: 6,235 useImperativeHandle: 9,236 useEffect: 7,237 useRef: 8,238 useLayoutEffect: 7239 }240 },241 {242 image: '/movie/animals.png',243 text: '"Ð¢Ð°Ð¹Ð½Ð°Ñ Ð¶Ð¸Ð·Ð½Ñ Ð´Ð¾Ð¼Ð°ÑниÑ
живоÑнÑÑ
2"',244 id: 8,245 points: {246 useState: 3,247 useReducer: 3,248 useCallback: 5,249 useImperativeHandle: 3,250 useEffect: 8,251 useRef: 7,252 useLayoutEffect: 4253 }254 }255 ]256 },257 {258 question: 'ÐÑбеÑи пеÑнÑ',259 type: 'withImage',260 options: [261 {262 image: '/song/despacito.png',263 text: 'Luis Fonsi: "Despacito"',264 id: 0,265 points: {266 useState: 6,267 useReducer: 5,268 useCallback: 6,269 useImperativeHandle: 6,270 useEffect: 5,271 useRef: 7,272 useLayoutEffect: 10273 }274 },275 {276 image: '/song/adele.png',277 text: 'Adele: "Rolling in the deep"',278 id: 1,279 points: {280 useState: 4,281 useReducer: 4,282 useCallback: 6,283 useImperativeHandle: 5,284 useEffect: 5,285 useRef: 10,286 useLayoutEffect: 3287 }288 },289 {290 image: '/song/beegees.png',291 text: 'Bee Gees: "How deep is your love"',292 id: 2,293 points: {294 useState: 5,295 useReducer: 4,296 useCallback: 7,297 useImperativeHandle: 4,298 useEffect: 10,299 useRef: 6,300 useLayoutEffect: 4301 }302 },303 {304 image: '/song/hellsbells.png',305 text: 'AC/DC: "Hells bells"',306 id: 3,307 points: {308 useState: 3,309 useReducer: 1,310 useCallback: 8,311 useImperativeHandle: 10,312 useEffect: 3,313 useRef: 5,314 useLayoutEffect: 1315 }316 },317 {318 image: '/song/survivor.png',319 text: 'Survivor: "Eye of the tiger"',320 id: 4,321 points: {322 useState: 1,323 useReducer: 5,324 useCallback: 10,325 useImperativeHandle: 5,326 useEffect: 2,327 useRef: 1,328 useLayoutEffect: 7329 }330 },331 {332 image: '/song/gaye.png',333 text: 'Marvin Gaye: "Lets get it on"',334 id: 5,335 points: {336 useState: 3,337 useReducer: 10,338 useCallback: 7,339 useImperativeHandle: 6,340 useEffect: 6,341 useRef: 1,342 useLayoutEffect: 6343 }344 },345 {346 image: '/song/pharell.png',347 text: 'Pharell Williams: "Happy"',348 id: 6,349 points: {350 useState: 10,351 useReducer: 6,352 useCallback: 5,353 useImperativeHandle: 2,354 useEffect: 5,355 useRef: 5,356 useLayoutEffect: 1357 }358 },359 {360 image: '/song/shortpairs.png',361 text: 'Shortparis: "СÑÑаÑно"',362 id: 7,363 points: {364 useState: 8,365 useReducer: 5,366 useCallback: 1,367 useImperativeHandle: 3,368 useEffect: 9,369 useRef: 8,370 useLayoutEffect: 7371 }372 },373 {374 image: '/song/arctic.png',375 text: 'Arctic Monkeys: "Four out of five"',376 id: 8,377 points: {378 useState: 3,379 useReducer: 9,380 useCallback: 5,381 useImperativeHandle: 3,382 useEffect: 1,383 useRef: 1,384 useLayoutEffect: 4385 }386 }387 ]388 },389 {390 question: 'Ðде ÑÑ Ð² пÑÑниÑÑ Ð²ÐµÑеÑом?',391 type: 'text',392 options: [393 {394 text: 'Со Ñвоей вÑоÑой половинкой',395 id: 2,396 points: {397 useState: 5,398 useReducer: 4,399 useCallback: 10,400 useImperativeHandle: 4,401 useEffect: 3,402 useRef: 4,403 useLayoutEffect: 4404 }405 },406 {407 text: 'ÐÑÑ
Ð°Ñ Ñ Ð´ÑÑзÑÑми',408 id: 3,409 points: {410 useState: 3,411 useReducer: 1,412 useCallback: 5,413 useImperativeHandle: 10,414 useEffect: 3,415 useRef: 4,416 useLayoutEffect: 1417 }418 },419 {420 text: 'Ðа Ñвиданке',421 id: 0,422 points: {423 useState: 10,424 useReducer: 5,425 useCallback: 8,426 useImperativeHandle: 6,427 useEffect: 7,428 useRef: 7,429 useLayoutEffect: 3430 }431 },432 {433 text: 'СплÑ',434 id: 4,435 points: {436 useState: 1,437 useReducer: 8,438 useCallback: 5,439 useImperativeHandle: 5,440 useEffect: 10,441 useRef: 1,442 useLayoutEffect: 7443 }444 },445 {446 text: 'ТÑÑÑÑÑÑ Ð² клÑбе',447 id: 5,448 points: {449 useState: 3,450 useReducer: 4,451 useCallback: 7,452 useImperativeHandle: 9,453 useEffect: 6,454 useRef: 10,455 useLayoutEffect: 8456 }457 },458 {459 text: 'СмоÑÑÑ ÐºÐ¸Ð½Ð¾ дома',460 id: 6,461 points: {462 useState: 1,463 useReducer: 6,464 useCallback: 5,465 useImperativeHandle: 2,466 useEffect: 5,467 useRef: 5,468 useLayoutEffect: 10469 }470 },471 {472 text: 'ÐÑÐ¼Ð°Ñ Ð¾ бÑвÑей',473 id: 1,474 points: {475 useState: 4,476 useReducer: 10,477 useCallback: 1,478 useImperativeHandle: 5,479 useEffect: 5,480 useRef: 4,481 useLayoutEffect: 3482 }483 },484 {485 text: 'ÐгÑÐ°Ñ Ð² наÑÑолки',486 id: 7,487 points: {488 useState: 8,489 useReducer: 5,490 useCallback: 1,491 useImperativeHandle: 3,492 useEffect: 9,493 useRef: 8,494 useLayoutEffect: 7495 }496 }497 ]498 },499 {500 question: 'ÐÑбеÑи ÑÑпеÑÑпоÑобноÑÑÑ',501 type: 'text',502 options: [503 {504 text: 'ÐевидимоÑÑÑ',505 id: 0,506 points: {507 useState: 10,508 useReducer: 5,509 useCallback: 8,510 useImperativeHandle: 6,511 useEffect: 7,512 useRef: 7,513 useLayoutEffect: 3514 }515 },516 {517 text: 'ÐÑÑеÑеÑÑвие во вÑемени',518 id: 1,519 points: {520 useState: 4,521 useReducer: 10,522 useCallback: 6,523 useImperativeHandle: 5,524 useEffect: 3,525 useRef: 4,526 useLayoutEffect: 3527 }528 },529 {530 text: 'ÐиÑаÑÑ Ð¿Ð¾Ð¿ÑлÑÑнÑе ÑвиÑÑ',531 id: 2,532 points: {533 useState: 4,534 useReducer: 4,535 useCallback: 10,536 useImperativeHandle: 4,537 useEffect: 3,538 useRef: 5,539 useLayoutEffect: 4540 }541 },542 {543 text: 'СÑпеÑÑила',544 id: 3,545 points: {546 useState: 3,547 useReducer: 1,548 useCallback: 8,549 useImperativeHandle: 10,550 useEffect: 3,551 useRef: 4,552 useLayoutEffect: 1553 }554 },555 {556 text: 'СÑпеÑÑолеÑаÑноÑÑÑ',557 id: 4,558 points: {559 useState: 1,560 useReducer: 3,561 useCallback: 4,562 useImperativeHandle: 5,563 useEffect: 10,564 useRef: 1,565 useLayoutEffect: 7566 }567 },568 {569 text: 'ТелепоÑÑаÑиÑ',570 id: 5,571 points: {572 useState: 3,573 useReducer: 4,574 useCallback: 7,575 useImperativeHandle: 3,576 useEffect: 6,577 useRef: 10,578 useLayoutEffect: 4579 }580 },581 {582 text: 'ЧиÑаÑÑ Ð¼ÑÑли',583 id: 6,584 points: {585 useState: 1,586 useReducer: 6,587 useCallback: 5,588 useImperativeHandle: 2,589 useEffect: 5,590 useRef: 5,591 useLayoutEffect: 10592 }593 },594 {595 text: 'ÐÑÑаÑÑ Ð¿Ð¾Ð´ водой',596 id: 7,597 points: {598 useState: 8,599 useReducer: 5,600 useCallback: 1,601 useImperativeHandle: 3,602 useEffect: 9,603 useRef: 8,604 useLayoutEffect: 7605 }606 }607 ]608 }609]610export const hooks = {611 useState: {612 description: 'Ð¢Ñ useState!',613 text: 'ÐозвÑаÑÐ°ÐµÑ Ð·Ð½Ð°Ñение Ñ ÑоÑÑоÑнием и ÑÑнкÑÐ¸Ñ Ð´Ð»Ñ ÐµÐ³Ð¾ обновлениÑ.',614 link: 'https://reactjs.org/docs/hooks-reference.html#usestate'615 },616 useReducer: {617 description: 'Ð¢Ñ useReducer!',618 text:619 'ÐлÑÑеÑнаÑива Ð´Ð»Ñ useState. ÐÑÐ¸Ð½Ð¸Ð¼Ð°ÐµÑ ÑедÑÑÐµÑ Ñипа (state, action) => newState и возвÑаÑÐ°ÐµÑ ÑекÑÑее ÑоÑÑоÑние в паÑе Ñ Ð¼ÐµÑодом dispatch. (ÐÑли Ð²Ñ Ð·Ð½Ð°ÐºÐ¾Ð¼Ñ Ñ Redux, Ð²Ñ Ñже знаеÑе, как ÑÑо ÑабоÑаеÑ.)',620 link: 'https://reactjs.org/docs/hooks-reference.html#usereducer'621 },622 useCallback: {623 description: 'Ð¢Ñ useCallback!',624 text: 'ÐозвÑаÑÐ°ÐµÑ Ð¼ÐµÐ¼Ð¾Ð¸Ð·Ð¸ÑованнÑй колбÑк.',625 link: 'https://reactjs.org/docs/hooks-reference.html#usecallback'626 },627 useImperativeHandle: {628 description: 'Ð¢Ñ useImperativeHandle!',629 text:630 'useImperativeHandle наÑÑÑÐ°Ð¸Ð²Ð°ÐµÑ Ð·Ð½Ð°Ñение ÑкземплÑÑа, коÑоÑое пÑедоÑÑавлÑеÑÑÑ ÑодиÑелÑÑким компоненÑам пÑи иÑполÑзовании ref. Ðак вÑегда, в болÑÑинÑÑве ÑлÑÑаев ÑледÑÐµÑ Ð¸Ð·Ð±ÐµÐ³Ð°ÑÑ Ð¸Ð¼Ð¿ÐµÑаÑивного кода, иÑполÑзÑÑÑего ÑÑÑлки. useImperativeHandle должен иÑполÑзоваÑÑÑÑ Ñ forwardRef:',631 link: 'https://reactjs.org/docs/hooks-reference.html#useimperativehandle'632 },633 useEffect: {634 description: 'Ð¢Ñ useEffect!',635 text:636 'ÐÑÐ¸Ð½Ð¸Ð¼Ð°ÐµÑ ÑÑнкÑиÑ, коÑоÑÐ°Ñ ÑодеÑÐ¶Ð¸Ñ Ð¸Ð¼Ð¿ÐµÑаÑивнÑй код, возможно, Ñ ÑÑÑекÑами.',637 link: 'https://reactjs.org/docs/hooks-reference.html#useeffect'638 },639 useRef: {640 description: 'Ð¢Ñ useRef!',641 text:642 'useRef возвÑаÑÐ°ÐµÑ Ð¸Ð·Ð¼ÐµÐ½ÑемÑй ref-обÑекÑ, ÑвойÑÑво .current коÑоÑого иниÑиализиÑÑеÑÑÑ Ð¿ÐµÑеданнÑм аÑгÑменÑом (initialValue). ÐозвÑаÑÑннÑй обÑÐµÐºÑ Ð±ÑÐ´ÐµÑ ÑоÑ
ÑанÑÑÑÑÑ Ð² ÑеÑение вÑего вÑемени жизни компоненÑа.',643 link: 'https://reactjs.org/docs/hooks-reference.html#useref'644 },645 useLayoutEffect: {646 description: 'Ð¢Ñ useLayoutEffect!',647 text:648 'СигнаÑÑÑа иденÑиÑна useEffect, но ÑÑÐ¾Ñ Ñ
Ñк запÑÑкаеÑÑÑ ÑинÑ
Ñонно поÑле вÑеÑ
изменений DOM. ÐÑполÑзÑйÑе его Ð´Ð»Ñ ÑÑÐµÐ½Ð¸Ñ Ð¼Ð°ÐºÐµÑа из DOM и ÑинÑ
Ñонного повÑоÑного ÑендеÑинга. ÐбновлениÑ, запланиÑованнÑе внÑÑÑи useLayoutEffect, бÑдÑÑ Ð¿Ð¾Ð»Ð½Ð¾ÑÑÑÑ Ð¿ÑÐ¸Ð¼ÐµÐ½ÐµÐ½Ñ ÑинÑ
Ñонно пеÑед Ñем, как бÑаÑÐ·ÐµÑ Ð¿Ð¾Ð»ÑÑÐ¸Ñ ÑÐ°Ð½Ñ Ð¾ÑÑÑеÑÑвиÑÑ Ð¾ÑÑиÑовкÑ.',649 link: 'https://reactjs.org/docs/hooks-reference.html#uselayouteffect'650 }...
useImperativeHandle.test.js
Source:useImperativeHandle.test.js
...18 it('Mutates given ref', () => {19 let ref;20 function Comp() {21 ref = useRef({});22 useImperativeHandle(ref, () => ({ test: () => 'test' }), []);23 return <p>Test</p>;24 }25 render(<Comp />, scratch);26 expect(ref.current).to.have.property('test');27 expect(ref.current.test()).to.equal('test');28 });29 it('calls createHandle after every render by default', () => {30 let ref,31 createHandleSpy = sinon.spy();32 function Comp() {33 ref = useRef({});34 useImperativeHandle(ref, createHandleSpy);35 return <p>Test</p>;36 }37 render(<Comp />, scratch);38 expect(createHandleSpy).to.have.been.calledOnce;39 render(<Comp />, scratch);40 expect(createHandleSpy).to.have.been.calledTwice;41 render(<Comp />, scratch);42 expect(createHandleSpy).to.have.been.calledThrice;43 });44 it('calls createHandle only on mount if an empty array is passed', () => {45 let ref,46 createHandleSpy = sinon.spy();47 function Comp() {48 ref = useRef({});49 useImperativeHandle(ref, createHandleSpy, []);50 return <p>Test</p>;51 }52 render(<Comp />, scratch);53 expect(createHandleSpy).to.have.been.calledOnce;54 render(<Comp />, scratch);55 expect(createHandleSpy).to.have.been.calledOnce;56 });57 it('Updates given ref when args change', () => {58 let ref,59 createHandleSpy = sinon.spy();60 function Comp({ a }) {61 ref = useRef({});62 useImperativeHandle(63 ref,64 () => {65 createHandleSpy();66 return { test: () => 'test' + a };67 },68 [a]69 );70 return <p>Test</p>;71 }72 render(<Comp a={0} />, scratch);73 expect(createHandleSpy).to.have.been.calledOnce;74 expect(ref.current).to.have.property('test');75 expect(ref.current.test()).to.equal('test0');76 render(<Comp a={1} />, scratch);77 expect(createHandleSpy).to.have.been.calledTwice;78 expect(ref.current).to.have.property('test');79 expect(ref.current.test()).to.equal('test1');80 render(<Comp a={0} />, scratch);81 expect(createHandleSpy).to.have.been.calledThrice;82 expect(ref.current).to.have.property('test');83 expect(ref.current.test()).to.equal('test0');84 });85 it('Updates given ref when passed-in ref changes', () => {86 let ref1, ref2;87 /** @type {(arg: any) => void} */88 let setRef;89 /** @type {() => void} */90 let updateState;91 const createHandleSpy = sinon.spy(() => ({92 test: () => 'test'93 }));94 function Comp() {95 ref1 = useRef({});96 ref2 = useRef({});97 const [ref, setRefInternal] = useState(ref1);98 setRef = setRefInternal;99 let [value, setState] = useState(0);100 updateState = () => setState((value + 1) % 2);101 useImperativeHandle(ref, createHandleSpy, []);102 return <p>Test</p>;103 }104 render(<Comp a={0} />, scratch);105 expect(createHandleSpy).to.have.been.calledOnce;106 updateState();107 rerender();108 expect(createHandleSpy).to.have.been.calledOnce;109 setRef(ref2);110 rerender();111 expect(createHandleSpy).to.have.been.calledTwice;112 updateState();113 rerender();114 expect(createHandleSpy).to.have.been.calledTwice;115 setRef(ref1);116 rerender();117 expect(createHandleSpy).to.have.been.calledThrice;118 });119 it('should not update ref when args have not changed', () => {120 let ref,121 createHandleSpy = sinon.spy(() => ({ test: () => 'test' }));122 function Comp() {123 ref = useRef({});124 useImperativeHandle(ref, createHandleSpy, [1]);125 return <p>Test</p>;126 }127 render(<Comp />, scratch);128 expect(createHandleSpy).to.have.been.calledOnce;129 expect(ref.current.test()).to.equal('test');130 render(<Comp />, scratch);131 expect(createHandleSpy).to.have.been.calledOnce;132 expect(ref.current.test()).to.equal('test');133 });134 it('should not throw with nullish ref', () => {135 function Comp() {136 useImperativeHandle(null, () => ({ test: () => 'test' }), [1]);137 return <p>Test</p>;138 }139 expect(() => render(<Comp />, scratch)).to.not.throw();140 });...
useImperativeHandle.js
Source:useImperativeHandle.js
...10 * 2. åæ°1: ç¶ç»ä»¶ä¼ éçrefå±æ§11 * 3. åæ°2: è¿åä¸ä¸ªå¯¹è±¡, 以ä¾ç»ç¶ç»ä»¶ä¸éè¿ref.currentè°ç¨è¯¥å¯¹è±¡ä¸çæ¹æ³12 * @type {React.ForwardRefExoticComponent<React.PropsWithoutRef<{}> & React.RefAttributes<unknown>>}13 */14// function useImperativeHandle(ref,factory){15// ref.current = factory()16// }17const JMInput = forwardRef((props, ref) => {18 const inputRef = useRef()19 // ä½ç¨: åå°ç¶ç»ä»¶è·åçDOMå
ç´ å±æ§,åªæ´é²ç»ç¶ç»ä»¶éè¦ç¨å°çDOMæ¹æ³20 // åæ°1: ç¶ç»ä»¶ä¼ éçrefå±æ§21 // åæ°2: è¿åä¸ä¸ªå¯¹è±¡,ç¶ç»ä»¶éè¿ref.currentè°ç¨å¯¹è±¡ä¸æ¹æ³22 // useImperativeHandle å½ä»¤å¼å¤çå¨23 useImperativeHandle(ref, () => ({24 focus: () => {25 inputRef.current.focus()26 },27 }))28 return <input type="text" ref={inputRef} />29})30export default function ImperativeHandleDemo() {31 // useImperativeHandle 主è¦ä½ç¨:ç¨äºåå°ç¶ç»ä»¶ä¸éè¿forward+useRefè·ååç»ä»¶DOMå
ç´ æ´é²çå±æ§è¿å¤32 // 为ä»ä¹ä½¿ç¨: å 为使ç¨forward+useRefè·ååå½æ°å¼ç»ä»¶DOMæ¶,è·åå°çdomå±æ§æ´é²ç太å¤äº33 // 解å³: 使ç¨uesImperativeHandle解å³,å¨åå½æ°å¼ç»ä»¶ä¸å®ä¹ç¶ç»ä»¶éè¦è¿è¡DOMæä½,åå°è·åDOMæ´é²çå±æ§è¿å¤34 const inputRef = useRef()35 // inputRef å
¶å®å°±æ¯æ们è¿åçé£ä¸ªå¯¹è±¡ {focus}36 return (37 <div>...
5-28.js
Source:5-28.js
...13*/14function Profile(props, ref) {15 const [name, setName] = useState("");16 const [age, setAge] = useState(0);17 useImperativeHandle(ref, () => ({18 addAge: (value) => setAge(age + value),19 getNameLength: () => name.length,20 }));21 return (22 <div>23 <h1> Child Component </h1>24 <div>25 <h2> ì¤ëª
</h2>26 <p> # ì½ë 5-28 ë¶ëª¨ ì»´í¬ëí¸ìì ì ê·¼ ê°ë¥í í¨ì를 구íí기</p>27 <p> * ì½ë 5-29 ë¶ëª¨ ì»´í¬ëí¸ìì í¸ì¶ë ìì ì»´í¬ëí¸</p>28 <p> * ë¶ëª¨ ì»´í¬ëí¸ìì ì ê·¼ ê°ë¥í í¨ì를 구í ë°©ë²</p>29 <p>30 {" "}31 <label> -- useImperativeHandle í
ì ëê° ë§¤ê°ë³ì ì§ì </label>...
hooks_useRef_useImperativeHandle转发.js
Source:hooks_useRef_useImperativeHandle转发.js
...35 const button2Ref = useRef();3637 // useImperativeHandleå®ä¹åè°å½æ°ï¼åé¢ä¸ä¸ªå½æ°çè¿å对象ä¼èµç»refä¸ï¼ä¹å°±æ¯è¿éç fancyInoutRef ï¼38 // å¤é¨å°±å¯ä»¥ç´æ¥éè¿ fancyInoutRef.current.getBtn1Width æ¿å°å¯¹è±¡éçå½æ°æ¥ä½¿ç¨39 useImperativeHandle(ref, () => ({40 getBtn1Width: () => {41 return button1Ref.current.offsetWidth;42 },43 getBtn2Width: () => {44 return button2Ref.current.offsetWidth;45 }46 }));47 return (48 <>49 <button ref={button1Ref} onClick={props.onClick1}>è·åæé®ç宽度11</button>50 <button ref={button2Ref} onClick={props.onClick2}>è·åæé®ç宽度2222</button>51 </>52 )53}
...
ImperativeHandle.js
Source:ImperativeHandle.js
...7// eslint-disable-next-line8const Input = forwardRef(9 ({ hasError, placeholder, value, handleChange }, ref) => {10 const inputRef = useRef(null);11 useImperativeHandle(ref, () => {12 return {13 focus: () => inputRef.current.focus(),14 };15 });16 return (17 <input18 type="text"19 value={value}20 placeholder={placeholder}21 onChange={(e) => handleChange(e.target.value)}22 ref={inputRef}23 style={{24 border: `1px solid ${hasError ? "red" : "black"}`,25 }}...
use-imperative-handle.jsx
Source:use-imperative-handle.jsx
1/**2 * useImperativeHandle(ref, createHandle, [deps])3 */4import { useImperativeHandle, forwardRef, useRef, useState } from 'react'5import { Typography, Button, Input } from 'antd'6const { Title } = Typography7function UseImperativeHandle() {8 const el = useRef(null)9 return (10 <>11 <Title>useImperativeHandle</Title>12 <Child ref={el}/>13 <Button onClick={() => {14 el.current.focus()15 console.log(el, 'el')16 }}>è·ååå
ç´ DOMèç¹</Button>17 </>18 )19}20const Child = forwardRef((props, ref) => {21 const [count, setCount] = useState(0)22 const [num, setNum] = useState(100)23 const inputRef = useRef(null)24 const spanEl = useRef(null)25 // 1.forwardRef26 useImperativeHandle(ref, () => ({27 value: '123',28 focus: () => {29 inputRef.current.focus()30 },31 spanEl,32 count,33 num34 // 第ä¸ä¸ªåæ° çæ§æ个å¼ååçæ¶å æä¼ææ°çç»æä¼ ç»ç¶ç»ä»¶35 // eslint-disable-next-line react-hooks/exhaustive-deps36 }), [num])37 return (38 <>39 {/*index.js:1 Warning: Function components cannot be given refs. Attempts to access this ref will fail. Did you mean to use React.forwardRef()?*/}40 {/*<Title ref={ref} level={3}>123</Title>*/}...
hooks-useImperativeHandle.js
Source:hooks-useImperativeHandle.js
...4_e = $RefreshSig$();5// ? should generate signature for built-in hooks6function ImperativeHandle(props, ref) {7 _d();8 const v = useImperativeHandle(ref, () => ({ a }));9}10_a = ImperativeHandle;11$RefreshReg$(_a, "ImperativeHandle");12_d(ImperativeHandle, "useImperativeHandle{v}");13ImperativeHandle = forwardRef(ImperativeHandle);14const HOC = forwardRef(_b = _e(function (props, ref) {15 _e();16 const v = useImperativeHandle(ref, () => ({ a }));17}, "useImperativeHandle{v}"));18$RefreshReg$(_b, "HOC$forwardRef");19_c = HOC;...
Using AI Code Generation
1const { chromium } = require('playwright');2const { useImperativeHandle } = require('playwright/lib/client/api');3(async () => {4 const browser = await chromium.launch();5 const page = await browser.newPage();6 const internalHandle = await page.evaluateHandle(() => window);7 const internalHandle2 = await useImperativeHandle(internalHandle);8 console.log(internalHandle2);9 await browser.close();10})();11const { chromium } = require('playwright');12const { useImperativeHandle } = require('playwright/lib/client/api');13(async () => {14 const browser = await chromium.launch();15 const page = await browser.newPage();16 const internalHandle = await useImperativeHandle(page);17 console.log(internalHandle);18 await browser.close();19})();20const { chromium } = require('playwright');21const { useImperativeHandle } = require('playwright/lib/client/api');22(async () => {23 const browser = await chromium.launch();24 const page = await browser.newPage();25 const internalHandle = await useImperativeHandle(page.mainFrame());26 console.log(internalHandle);27 await browser.close();28})();
Using AI Code Generation
1const { useImperativeHandle } = require('playwright/lib/server/dom');2const { useImperativeHandle } = require('playwright/lib/server/dom');3const { useImperativeHandle } = require('playwright/lib/server/dom');4const { useImperativeHandle } = require('playwright/lib/server/dom');5const { useImperativeHandle } = require('playwright/lib/server/dom');6const { useImperativeHandle } = require('playwright/lib/server/dom');7const { useImperativeHandle } = require('playwright/lib/server/dom');8const { useImperativeHandle } = require('playwright/lib/server/dom');9const { useImperativeHandle } = require('playwright/lib/server/dom');10const { useImperativeHandle } = require('playwright/lib/server/dom');11const { useImperativeHandle } = require('playwright/lib/server/dom');12const { useImperativeHandle } = require('playwright/lib/server/dom');13const { useImperativeHandle } = require('playwright/lib/server/dom');14const { useImperativeHandle } = require('playwright/lib/server/dom');15const { useImperativeHandle } = require('playwright/lib/server/dom');16const {
Using AI Code Generation
1const { useImperativeHandle } = require('playwright-core/lib/server/frames');2const { useImperativeHandle } = require('playwright-core/lib/server/frames');3const { useImperativeHandle } = require('playwright-core/lib/server/frames');4const { useImperativeHandle } = require('playwright-core/lib/server/frames');5const { useImperativeHandle } = require('playwright-core/lib/server/frames');6const { useImperativeHandle } = require('playwright-core/lib/server/frames');7const { useImperativeHandle } = require('playwright-core/lib/server/frames');8const { useImperativeHandle } = require('playwright-core/lib/server/frames');9const { useImperativeHandle } = require('playwright-core/lib/server/frames');10const { useImperativeHandle } = require('playwright-core/lib/server/frames');11const { useImperativeHandle } = require('playwright-core/lib/server/frames');12const { useImperativeHandle } = require('playwright-core/lib/server/frames');13const { useImperativeHandle } = require('playwright-core/lib/server/frames');14const { useImperativeHandle } = require('playwright-core/lib/server/frames');15const { useImperativeHandle } = require('playwright-core/lib/server/frames');
Using AI Code Generation
1const { chromium } = require('playwright');2const { useImperativeHandle } = require('playwright/lib/server/supplements/handlers/handler');3(async () => {4 const browser = await chromium.launch();5 const context = await browser.newContext();6 const page = await context.newPage();7 const frame = page.mainFrame();8 const elementHandle = await frame.$('text=Get started');9 const element = await elementHandle.asElement();10 const internalHandler = await useImperativeHandle(element);11 const internalElement = await internalHandler._elementPromise;12 console.log(internalElement);13 await browser.close();14})();15ElementHandle {16 _elementPromise: Promise { <pending> },17 _context: BrowserContext {18 _browser: Browser {19 _connection: Connection {20 _events: [Object: null prototype] {},21 },22 _options: {23 },
Using AI Code Generation
1const {chromium} = require('playwright');2const {useImperativeHandle} = require('playwright/lib/server/injected/injectedScript');3(async () => {4 const browser = await chromium.launch();5 const context = await browser.newContext();6 const page = await context.newPage();7 await page.screenshot({ path: 'example.png' });8 await browser.close();9})();
Using AI Code Generation
1import { chromium, firefox, webkit } from 'playwright';2import { useImperativeHandle } from 'playwright-core/lib/server/chromium/crBrowser';3(async () => {4 const browser = await chromium.launch();5 const page = await browser.newPage();6 const video = await page.$('video');7 await video.useImperativeHandle();8 await browser.close();9})();10 at Browser.useImperativeHandle (C:\Users\mohit\Documents\Playwright\playwright-core\lib\server\chromium\crBrowser.js:58:19)11 at processTicksAndRejections (internal/process/task_queues.js:97:5)12 at async Object.<anonymous> (C:\Users\mohit\Documents\Playwright\test.js:10:5)
Using AI Code Generation
1const { useImperativeHandle } = require('playwright/lib/client/selectorEngine');2const { Selector } = require('playwright');3useImperativeHandle('selector', (selector, action) => {4 if (action === 'query') {5 return selector;6 }7 if (action === 'queryAll') {8 return [selector];9 }10 throw new Error(`Unknown action "${action}"`);11});12(async () => {13 const browser = await chromium.launch({ headless: false });14 const context = await browser.newContext();15 const page = await context.newPage();16 const selector = await Selector('input').addCustomMethods({17 async fill(page, text) {18 await page.fill(this, text);19 },20 });21 await selector.fill(page, 'Hello, World!');22 await browser.close();23})();
Using AI Code Generation
1const { chromium } = require('playwright');2(async () => {3 const browser = await chromium.launch();4 const page = await browser.newPage();5 const internalPage = page._delegate;6 const internalBrowser = browser._delegate;7 const internalBrowserContext = internalBrowser._defaultContext;8 const internalBrowserContextController = internalBrowserContext._browserContextController;9 const internalBrowserContextControllerPage = internalBrowserContextController._page;10 const internalBrowserContextControllerPageFrame = internalBrowserContextControllerPage.mainFrame();11 const internalBrowserContextControllerPageFrameSession = internalBrowserContextControllerPageFrame._session;12 const internalBrowserContextControllerPageFrameSessionConnection = internalBrowserContextControllerPageFrameSession._connection;13 const internalBrowserContextControllerPageFrameSessionConnectionTransport = internalBrowserContextControllerPageFrameSessionConnection._transport;14 const internalBrowserContextControllerPageFrameSessionConnectionTransportWebSocket = internalBrowserContextControllerPageFrameSessionConnectionTransport._ws;15 const internalBrowserContextControllerPageFrameSessionConnectionTransportWebSocketUrl = internalBrowserContextControllerPageFrameSessionConnectionTransportWebSocket._url;16 console.log(internalBrowserContextControllerPageFrameSessionConnectionTransportWebSocketUrl);17 await browser.close();18})();19const { chromium } = require('playwright');20(async () => {21 const browser = await chromium.launch();22 const page = await browser.newPage();23 const internalPage = page._delegate;24 const internalBrowser = browser._delegate;25 const internalBrowserContext = internalBrowser._defaultContext;26 const internalBrowserContextController = internalBrowserContext._browserContextController;27 const internalBrowserContextControllerPage = internalBrowserContextController._page;28 const internalBrowserContextControllerPageFrame = internalBrowserContextControllerPage.mainFrame();29 const internalBrowserContextControllerPageFrameSession = internalBrowserContextControllerPageFrame._session;30 const internalBrowserContextControllerPageFrameSessionConnection = internalBrowserContextControllerPageFrameSession._connection;31 const internalBrowserContextControllerPageFrameSessionConnectionTransport = internalBrowserContextControllerPageFrameSessionConnection._transport;
Using AI Code Generation
1const { chromium } = require('playwright');2const { useImperativeHandle } = require('playwright/lib/server/supplements/recorder/recorderSupplement');3(async () => {4 const browser = await chromium.launch({headless: false});5 const context = await browser.newContext();6 const page = await context.newPage();7 const pageObject = useImperativeHandle(page);8 console.log(pageObject);9 await browser.close();10})();11Page {12 _browserContext: BrowserContext {13 _options: {14 _recordVideoSize: { width: 1280, height: 720 },15 _timeoutSettings: TimeoutSettings { _defaultTimeout: 30000 },16 _env: {},
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