How to use EvaluateAsync method of Microsoft.Playwright.Core.Worker class

# Install the CLI once.
dotnet tool install --global Microsoft.Playwright.CLI
# Install the browsers
playwright install

(The current error description is a bug in 1.14, it gets fixed with 1.15.)

You can use the selecting selectors based on layout for this.

await page.Locator("span:below(:text(\" Status :\"))").TextContentAsync()

Your page might be recreating the DOM. To overcome that you can use the locator feature from playwright.

var locator = page.Locator("inputSelector");
await locator.ClickAsync();

The solution I found to this was to simply remove the part of the test name in parenthesis, which caused the dotnet test command to run every test with a matching name. I then added a random guid to the name of each test trace that was generated in order to prevent them from overwriting eachother.

# Install the CLI once.
dotnet tool install --global Microsoft.Playwright.CLI
# Install the browsers
playwright install

(The current error description is a bug in 1.14, it gets fixed with 1.15.)

You can use the selecting selectors based on layout for this.

await page.Locator("span:below(:text(\" Status :\"))").TextContentAsync()

The error came from me not correctly understanding Docker stages. Here a fixed Dockerfile, where I installed Playwright in the base stage:

FROM mcr.microsoft.com/dotnet/aspnet:6.0 AS base
RUN apt-get update
RUN apt-get -y install curl gnupg
RUN curl -sL https://deb.nodesource.com/setup_16.x  | bash -
RUN apt-get -y install nodejs
RUN npx playwright install
RUN apt-get update && apt-get install -y --no-install-recommends \
    fonts-liberation\
    libasound2\
    libatk-bridge2.0-0\
    libatk1.0-0\
    libatspi2.0-0\
    libcairo2\
    libcups2\
    libdbus-1-3\
    libdrm2\
    libgbm1\
    libglib2.0-0\
    libgtk-3-0\
    libnspr4\
    libnss3\
    libpango-1.0-0\
    libx11-6\
    libxcb1\
    libxcomposite1\
    libxdamage1\
    libxext6\
    libxfixes3\
    libxrandr2
WORKDIR /app

FROM mcr.microsoft.com/dotnet/sdk:6.0-focal  AS build
WORKDIR /src
COPY ["Dashboard/Dashboard.csproj", "Dashboard/"]
RUN dotnet restore "Dashboard/Dashboard.csproj"
COPY . .
WORKDIR "/src/Dashboard"
RUN dotnet build "Dashboard.csproj" -c Release -o /app/build
FROM build AS publish
RUN dotnet publish "Dashboard.csproj" -c Release -o /app/publish

FROM base AS final
WORKDIR /app
COPY --from=publish /app/publish .
ENTRYPOINT ["dotnet", "Dashboard.dll"]

Using a selector that finds a list of locators in Playwright is exactly the same as calling .FindElements() in selenium, except that Playwright does not have a specifically named method like .FindLocators().

Playwright - a selector that matches multiple elements returns a list of locators, which you then iterate over:

var rows = page.GetByRole(AriaRole.Listitem);
var count = await rows.CountAsync();
for (int i = 0; i < count; ++i)
  Console.WriteLine(await rows.Nth(i).TextContentAsync());

Selenium - FindElements returns a list of elements that you have to iterate over.

IList < IWebElement > elements = driver.FindElements(By.TagName("p"));
foreach(IWebElement e in elements) {
  System.Console.WriteLine(e.Text);
}

Finally I was able to find a way to run the tests inside a Docker container using a custom image. Here is what I've done:

FROM mcr.microsoft.com/dotnet/sdk:5.0.404-focal AS build
WORKDIR /src
COPY ["PlaywrightSharp/PlaywrightSharp.csproj", "PlaywrightSharp/"]
RUN dotnet restore "PlaywrightSharp/PlaywrightSharp.csproj"

COPY . .
WORKDIR "/src/PlaywrightSharp"

RUN apt-get update -yq && apt-get upgrade -yq && apt-get install -yq curl git nano
RUN curl -sL https://deb.nodesource.com/setup_16.x | bash - && apt-get install -yq nodejs build-essential
RUN npm install -g npm

RUN apt-get install -y wget xvfb unzip

# Set up the Chrome PPA
RUN wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | apt-key add -
RUN echo "deb http://dl.google.com/linux/chrome/deb/ stable main" >> /etc/apt/sources.list.d/google.list

# Update the package list and install chrome
RUN apt-get update -y
RUN apt-get install -y google-chrome-stable
RUN apt-get install -y firefox

#RUN dotnet add package Microsoft.Playwright
RUN dotnet build "PlaywrightSharp.csproj" -c Release -o /app/build
RUN npx playwright install-deps
RUN npx playwright install


FROM build AS testrunner
WORKDIR "/src/PlaywrightSharp"
CMD ["dotnet", "test", "--no-restore", "--settings:Firefox.runsettings", "--logger:trx"]

It looks like npx playwright install-deps was not enough to run the tests and I had to install Chrome and Firefox also.