如何列出JavaScript对象的属性？

本文翻译自：How to list the properties of a JavaScript object?

Say I create an object thus: 假设我创建了一个对象：

var myObject =
        {"ircEvent": "PRIVMSG", "method": "newURI", "regex": "^http://.*"};

What is the best way to retrieve a list of the property names? 检索属性名称列表的最佳方法是什么？ ie I would like to end up with some variable 'keys' such that: 即我想最终得到一些变量'键'，这样：

keys == ["ircEvent", "method", "regex"]

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#1楼

参考：https://stackoom.com/question/s76/如何列出JavaScript对象的属性

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#2楼

This will work in most browsers, even in IE8 , and no libraries of any sort are required. 这适用于大多数浏览器，即使在IE8中也是如此，并且不需要任何类型的库。 var i is your key. var i是你的关键。

var myJSONObject =  {"ircEvent": "PRIVMSG", "method": "newURI", "regex": "^http://.*"}; 
var keys=[];
for (var i in myJSONObject ) { keys.push(i); }
alert(keys);

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#3楼

在支持js 1.8的浏览器下：

[i for(i in obj)]

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#4楼

Could do it with jQuery as follows: 可以用jQuery做到如下：

var objectKeys = $.map(object, function(value, key) {
  return key;
});

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#5楼

Mozilla has full implementation details on how to do it in a browser where it isn't supported, if that helps: Mozilla有关于如何在不支持的浏览器中执行此操作的完整实现详细信息 ，如果有帮助：

if (!Object.keys) {
  Object.keys = (function () {
    var hasOwnProperty = Object.prototype.hasOwnProperty,
        hasDontEnumBug = !({toString: null}).propertyIsEnumerable('toString'),
        dontEnums = [
          'toString',
          'toLocaleString',
          'valueOf',
          'hasOwnProperty',
          'isPrototypeOf',
          'propertyIsEnumerable',
          'constructor'
        ],
        dontEnumsLength = dontEnums.length;

    return function (obj) {
      if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) throw new TypeError('Object.keys called on non-object');

      var result = [];

      for (var prop in obj) {
        if (hasOwnProperty.call(obj, prop)) result.push(prop);
      }

      if (hasDontEnumBug) {
        for (var i=0; i < dontEnumsLength; i++) {
          if (hasOwnProperty.call(obj, dontEnums[i])) result.push(dontEnums[i]);
        }
      }
      return result;
    };
  })();
}

You could include it however you'd like, but possibly in some kind of extensions.js file at the top of your script stack. 您可以根据需要包含它，但可能包含在脚本堆栈顶部的某种extensions.js文件中。

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#6楼

I'm a huge fan of the dump function. 我是转储功能的忠实粉丝。

http://ajaxian.com/archives/javascript-variable-dump-in-coldfusion http://ajaxian.com/archives/javascript-variable-dump-in-coldfusion