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Javascript JS：循环外的变量（数组）-发生了什么？_Javascript - Fatal编程技术网
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Javascript JS：循环外的变量（数组）-发生了什么？

javascript

Javascript JS：循环外的变量（数组）-发生了什么？,javascript,Javascript,请你纠正一下我做错的事好吗 var ipLocations = []; // variable in question for (i = 0; i < ips.length; i++) { (function(i) { setTimeout(function() { $.getJSON(.... }; alert(ipLocations); // becoming '' here:( var ipLocations=[]；//有问题

请你纠正一下我做错的事好吗

var ipLocations = []; // variable in question

for (i = 0; i < ips.length; i++) {
    (function(i) {
        setTimeout(function() {

            $.getJSON(....

};

alert(ipLocations); // becoming '' here:(

var ipLocations=[]；//有问题的变量
对于（i=0；i
为什么ipLocations在这里？

for循环中的代码是非阻塞代码……这意味着您的警报将在
getJSON
和
setTimeout
回调填充
ipLocations
之前发出

您可以通过使用或回调函数来修复它，该函数将检查所有请求是否已完成，如果已完成，则显示警报。

嘿…别那么刻薄…告诉什么是错的？？什么是错的？？