75 lines
2.2 KiB
Markdown
75 lines
2.2 KiB
Markdown
---
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title: Object getOwnPropertyNames
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localeTitle: Object getOwnPropertyNames
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---
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`Object.getOwnPropertyNames()`方法返回直接在给定对象上找到的所有属性（可枚举或不可枚举`Object.getOwnPropertyNames()`的数组。
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## 句法
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```
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Object.getOwnPropertyNames(obj)
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```
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### 参数
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**OBJ**
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将返回其可枚举_和不可枚举的_自身属性的对象。
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[MDN链接](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/getOwnPropertyNames) | [MSDN链接](https://msdn.microsoft.com/en-us/LIBRary/ff688126%28v=vs.94%29.aspx)
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## 描述
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`Object.getOwnPropertyNames()`返回一个数组，其元素是与直接在对象上找到的可枚举_和不可枚举_属性相对应的字符串。数组中可枚举属性的排序与`for...in`循环（或`Object.keys()` ）在对象属性上公开的顺序一致。未定义数组中以及可枚举属性中的非可枚举属性的顺序。
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## 例子
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```
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var arr = ['a', 'b', 'c'];
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console.log(Object.getOwnPropertyNames(arr).sort()); // logs '0,1,2,length'
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// Array-like object
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var obj = { 0: 'a', 1: 'b', 2: 'c' };
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console.log(Object.getOwnPropertyNames(obj).sort()); // logs '0,1,2'
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// Logging property names and values using Array.forEach
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Object.getOwnPropertyNames(obj).forEach(function(val, idx, array) {
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console.log(val + ' -> ' + obj[val]);
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});
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// logs
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// 0 -> a
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// 1 -> b
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// 2 -> c
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// non-enumerable property
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var my_obj = Object.create({}, {
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getFoo: {
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value: function() { return this.foo; },
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enumerable: false
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}
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});
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my_obj.foo = 1;
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console.log(Object.getOwnPropertyNames(my_obj).sort()); // logs 'foo,getFoo'
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function Pasta(grain, size, shape) {
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this.grain = grain;
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this.size = size;
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this.shape = shape;
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}
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var spaghetti = new Pasta("wheat", 2, "circle");
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var names = Object.getOwnPropertyNames(spaghetti).filter(CheckKey);
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document.write(names);
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// Check whether the first character of a string is 's'.
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function CheckKey(value) {
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var firstChar = value.substr(0, 1);
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if (firstChar.toLowerCase() == 's')
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return true;
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else
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return false;
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}
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// Output:
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// size,shape
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``` |