从注入的页面执行脚本主机 [英] Executing host script from an injected page
问题描述
我正在写一个Safari浏览器扩展,增加了一些功能来一个网页,我没有自己。我想为我注入了JavaScript网页能够激发宿主页面使用了一些JavaScript函数,但它不工作。在控制台我得到的消息的ReferenceError:找不到变量:FUNCTION_NAME
I'm writing a Safari Extension that adds some functionality to a web page that I don't own. I would like for my injected JavaScript page to be able to fire some JavaScript functions the host page uses, but it doesn't work. On the Console I get the message ReferenceError: Can't find variable: function_name
.
我的脚本被指定为一个结束脚本,让整个页面应加载。该功能也从的onclick()
处理程序调用页面上,像这样:
My script is specified to be an End Script, so the whole page should be loaded. The function is also called from an onclick()
handler on the page, like so:
onclick="function_name($(this).up());"
我能到该页面元素的引用,但是当我打电话 element.onclick()
我得到另一个错误:类型错误:'未定义不是(评估函数'$(本).UP()')
。
奇怪的是,当我调用JavaScript函数从一个AppleScript(做的JavaScript函数名()中页
),它工作正常。我怎样才能触发这些功能呢?
Oddly, when I call the JavaScript function from an AppleScript (do JavaScript "function_name()" in page
) it works fine. How can I trigger these functions?
推荐答案
我可以从canisbos延长答复。你可以用PostMessage函数插入脚本通信。
I can extend answer from canisbos. You can communicate with the inserted script with the PostMessage function.
注入脚本:
//insert script to page
var myScriptElement = document.createElement('script');
myScriptElement.innerHTML =
'window.addEventListener("message", function(e) {' +
' if (e.data.msg == "do") {' +
' foo(e.data.info);' +
' postMessage({msg: "done", info: "answer"}, "*");' +
' };' +
'}, false);'
document.querySelector('head').appendChild(myScriptElement);
//add answers listener
window.addEventListener('message', function(e) {
if (e.data.msg == 'done') {
console.log(e.data.info);
};
}, false);
//add the testing function on the body click
document.addEventListener('click', function (e) {
//call inserted script
postMessage({msg: 'do', info: 'from inject'}, '*');
}, false);
测试HTML页面:
Test html page:
<html>
<script>
function foo(text) {
console.log(text);
};
</script>
<body>
<button id='button' onclick='foo("from page")'>test</button>
</body>
</html>
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