PowerScript Reference
PowerScript Functions

Description

Sends the web message in the JSON format to the top-level document in WebBrowser asynchronously.

Applies to

WebBrowser control

Syntax

objectname.PostJsonWebMessage (sring json)

"{\"a\": \"b\"}"

Return value

Integer.

Returns 1 if the function succeeds and a negative value if an error occurs. If any argument's value is null, the method returns null.

Usage

In the top-level document of WebBrowser, the web message can be subscribed or unsubscribed through the following JavaScript:

window.chrome.webview.addEventListener('message', handler)

window.chrome.webview.removeEventListener('message', handler)

"handler" is the process of handling specific events. The event args is an instance of MessageEvent defined in the HTML5 specification. The event args data property is the JSON string sent by this function PostJsonWebMessage, and the JSON string has been parsed into the corresponding JavaScript object. If a navigation occurs before the message reaches the page, the message will be discarded. This function will trigger the WebMessageReceived event.

Here is a JavaScript code example:

window.chrome.webview.addEventListener('message', arg => {
            if ("SetColor" in arg.data) {
                document.getElementById("colorable").style.color = arg.data.SetColor;
            }
            if ("WindowBounds" in arg.data) {
                document.getElementById("window-bounds").value = arg.data.WindowBounds;
            }
        });

        function SetTitleText() {
            let titleText = document.getElementById("title-text");
            window.chrome.webview.postMessage(`SetTitleText ${titleText.value}`);
        }
        function GetWindowBounds() {
            window.chrome.webview.postMessage("GetWindowBounds");
        }

Examples

This example sends the specified web message in JSON format to the top-level document to set the color:

//window.chrome.webview.addEventListener('message', arg => {
//   window.chrome.webview.postMessage(JSON.stringify(arg.data));
//        });
Integer li_return

li_return = wb_1.PostJsonWebMessage('{"SetColor":"blue"}')

See also

NavigateToString

OpenDefaultDownloadDialog

PostStringWebMessage