正文 1385字数 72,288阅读

1. 取整同时转成数值型：
'10.567890'|0
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    结果: 10

    '10.567890'^0
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      结果: 10

      -2.23456789|0
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        结果: -2

        ~~-2.23456789
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          结果: -2

          2. 日期转数值：

          var d = +new Date(); //1295698416792
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            3. 类数组对象转数组：

            var arr = [].slice.call(arguments)
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              4. 漂亮的随机码：

              Math.random().toString(16).substring(2); //14位 Math.random().toString(36).substring(2); //11位
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                5. 合并数组：

                var a = [1,2,3]; var b = [4,5,6]; Array.prototype.push.apply(a, b); uneval(a); //[1,2,3,4,5,6]
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                  6. 用0补全位数：

                  function prefixInteger(num, length) { return (num / Math.pow(10, length)).toFixed(length).substr(2); }
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                    7. 交换值：

                    a= [b, b=a][0];
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                      8. 将一个数组插入另一个数组的指定位置：

                      var a = [1,2,3,7,8,9]; var b = [4,5,6]; var insertIndex = 3; a.splice.apply(a, Array.concat(insertIndex, 0, b)); // a: 1,2,3,4,5,6,7,8,9
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                        9. 删除数组元素：

                        var a = [1,2,3,4,5]; a.splice(3,1);
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                          10. 快速取数组最大和最小值

                          Math.max.apply(Math, [1,2,3]) //3 Math.min.apply(Math, [1,2,3]) //1
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                            11. 条件判断：

                            var a = b && 1;
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                              相当于

                              if (b) { a = 1 } var a = b || 1;
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                                相当于

                                if (b) { a = b; } else { a = 1; }
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                                  12. 判断IE:
                                  var ie = /*@cc_on !@*/false;
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