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javascript foreach()遍历打印输出数组元素值

打印数组内容:
代码:
--------------------------------------------------------------------------------

 代码如下 复制代码

function printElt(element, index, array) {
    document.writeln("[" + index + "] is " + element + "<br />");
}
[2, 5, 9].forEach(printElt);
// Prints:
// [0] is 2
// [1] is 5
// [2] is 9
结果:
--------------------------------------------------------------------------------
 [0] is 2
[1] is 5
[2] is 9


用对象的方法打印数组内容:
代码:
--------------------------------------------------------------------------------

 代码如下 复制代码

var writer = {
 sb:       [],
 write:    function (s) {
  this.sb.push(s);
 },
 writeln:  function (s) {
  this.write(s + "<br />");
 },
 toString: function () {
  return this.sb.join("");
 }
};

[2, 5, 9].forEach(writer.writeln, writer);
document.writeln(writer.toString());
// Prints:
// 2
// 5
// 9
结果:
--------------------------------------------------------------------------------
 2
5
9


下面看实例

 代码如下 复制代码

<script language="JavaScript" type="text/javascript">
 
// 说明:Javascript Array 的 forEach 方法
// 整理:http://www.zzzyk.com
// 来源:http://www.hzhuti.com
 
if (!Array.prototype.forEach)
{
    Array.prototype.forEach = function(fun /*, thisp*/)
    {
        var len = this.length;
        if (typeof fun != "function")
            throw new TypeError();
 
        var thisp = arguments[1];
        for (var i = 0; i < len; i++)
        {
            if (i in this)
                fun.call(thisp, this[i], i, this);
        }
    };
}
 
</script>

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