Playwright.JSHandle (playwright v1.18.0-alpha.1) View Source

Playwright.JSHandle represents an in-page JavaScript object. JSHandles can be created with Playwright.Page.evaluate_handle/3.

Example

handle = Page.evaluate_handle(page, "() => window")

JSHandle prevents the referenced JavaScript object from being garbage collected unless the handle is disposed with Playwright.JSHandle.dispose/1. JSHandles are auto-disposed when their origin frame gets navigated or the parent context gets destroyed.

JSHandle instances can be used as arguments to:

Link to this section Summary

Types

t()

%Playwright.JSHandle{}

Functions

as_element(handle)

Returns either nil or the object handle itself, if the object handle is an instance of Playwright.ElementHandle.

evaluate(handle, expression, arg \\ nil)

evaluate_handle(handle, expression, arg \\ nil)

Returns the return value from executing param: expression in the browser as a Playwright.JSHandle.

init(owner, initializer)

Optional callback implementation for Playwright.ChannelOwner.init/2.

string(handle)

Link to this section Types

t()

Specs

t() :: %Playwright.JSHandle{
  guid: term(),
  initializer: term(),
  listeners: term(),
  parent: term(),
  preview: term(),
  session: term(),
  type: term()
}

%Playwright.JSHandle{}

Link to this section Functions

as_element(handle)

Specs

as_element(struct()) :: Playwright.ElementHandle.t() | nil

Returns either nil or the object handle itself, if the object handle is an instance of Playwright.ElementHandle.

evaluate(handle, expression, arg \\ nil)

evaluate_handle(handle, expression, arg \\ nil)

Specs

evaluate_handle(t() | Playwright.ElementHandle.t(), binary(), any()) ::
  Playwright.ElementHandle.t()

Returns the return value from executing param: expression in the browser as a Playwright.JSHandle.

This function passes the handle as the first argument to param: expression.

The only difference between Playwright.JSHandle.evaluate/3 and Playwright.JSHandle.evaluate_handle/3 is that evaluate_handle returns Playwright.JSHandle.

If the expression passed to Playwright.JSHandle.evaluate_handle/3 returns a Promise, Playwright.JSHandle.evaluate_handle/3 waits for the promise to resolve and return its value.

See Playwright.Page.evaluate_handle/3 for more details.

Returns

Playwright.ElementHandle.t()

Arguments

key/name	type		description
`expression`	param	`binary()`	Function to be evaluated in the page context.
`arg`	param	`any()`	Argument to pass to `expression` `(optional)`

init(owner, initializer)

Specs

init(
  struct(),
  map()
) :: {atom(), struct()}

Optional callback implementation for Playwright.ChannelOwner.init/2.

If implemented, the callback will receive:

The newly created "channel owner" struct.
The :initializer received from the Playwright browser server.

The implementation has the option of "patching" the struct as stored in the catalog, and/or binding event handlers.

Example

def init(%{session: session} = owner, _initializer) do
  Channel.bind(session, {:guid, owner.guid}, :close, fn event ->
    Logger.warn("Closing #{inspect(event.target)}")
  end)

  {:ok, %{owner | version: "1.2.3"}}
end

Returns

{:ok, struct()}

Arguments

key/name	type		description
`owner`	param	`struct()`	The newly created channel owner (resource).
`initializer`	param	`struct()`	The initializer received from with the channel owner instance was derived.