javascript 在子窗口中访问父局部变量
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Access parent local variable in child window
提问by mOna
I would like to use a local variable of a parent in child window. I used parent.window.openerbut it returns undefined.
我想在子窗口中使用父级的局部变量。我用过，parent.window.opener但它返回undefined.
This is my code:
这是我的代码：
<script type="text/javascript">
var selectedVal;
$(document).ready(function () {
//....
//...
if ($(this).val() == "byActor"){
$("#tags").focus();
$("#tags").autocomplete({
source: "actorsauto.php",
minLength: 2,
focus: function( event, ui ){
event.preventDefault();
return false;
},
select: function (event, ui){
var selectedVal = ui.item.value;
alert(selectedVal);
}
});
});
$('#btnRight').on('click', function (e) {
popupCenter("movieByactor.php","_blank","400","400");
});
</script>
</body>
</html>
and this is a child:
这是一个孩子：
<body>
<script type="text/javascript">
var selectedVal = parent.window.opener.selectedVal;
alert(selectedVal);
</script>
</body>
回答by max
You can't - the whole idea with local variables is that they are only available in whatever function scope they are declared in - and functions inside that function.
你不能 - 局部变量的整个想法是它们只能在它们声明的任何函数范围内可用 - 以及该函数内的函数。
In your case select selectedValis only available inside this function declaration:
在您的情况下， selectselectedVal仅在此函数声明中可用：
select: function (event, ui){
var selectedVal = ui.item.value;
alert(selectedVal);
}
To use it outside this scope you need to make it global by attaching it to the window:
要在此范围之外使用它，您需要通过将其附加到窗口来使其成为全局：
window.selectedVal = 'somevalue';
You can also make variables implicitly global by leaving out the varkeyword - however this is a poor practice and is not allowed in strict mode.
您还可以通过省略var关键字来使变量隐式全局化- 但这是一种糟糕的做法，并且在严格模式下是不允许的。
This will allow you to you access window.selectedValby:
这将允许您window.selectedVal通过以下方式访问：
window.opener.selectedVal // for windows opened with window.open()
window.parent.selectedVal // iframe parent document
回答by Vano Atabegashvili
try this:
试试这个：
<body>
<script type="text/javascript">
var selectedVal = window.opener.selectedVal;
alert(selectedVal);
</script>
</body>
