JS_Array扩展

 

来源:https://developer.mozilla.org/en/New_in_JavaScript_1.6#Array_extras

 

indexOf

 

if (!Array.prototype.indexOf) { Array.prototype.indexOf = function(elt /*, from*/) { var len = this.length >>> 0; var from = Number(arguments[1]) || 0; from = (from < 0) ? Math.ceil(from) : Math.floor(from); if (from < 0) from += len; for (; from < len; from++) { if (from in this && this[from] === elt) return from; } return -1; }; }

 

every

 

if (!Array.prototype.every) { Array.prototype.every = function(fun /*, thisp*/) { var len = this.length >>> 0; 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)) return false; } return true; }; }

 

filter

 

if (!Array.prototype.filter) { Array.prototype.filter = function(fun /*, thisp*/) { var len = this.length >>> 0; if (typeof fun != "function") throw new TypeError(); var res = []; var thisp = arguments[1]; for (var i = 0; i < len; i++) { if (i in this) { var val = this[i]; // in case fun mutates this if (fun.call(thisp, val, i, this)) res.push(val); } } return res; }; }

 

forEach

 

if (!Array.prototype.forEach) { Array.prototype.forEach = function(fun /*, thisp*/) { var len = this.length >>> 0; 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); } }; }

 

map

 

if (!Array.prototype.map) { Array.prototype.map = function(fun /*, thisp*/) { var len = this.length >>> 0; if (typeof fun != "function") throw new TypeError(); var res = new Array(len); var thisp = arguments[1]; for (var i = 0; i < len; i++) { if (i in this) res[i] = fun.call(thisp, this[i], i, this); } return res; }; }

 

some

 

if (!Array.prototype.some) { Array.prototype.some = function(fun /*, thisp*/) { var i = 0, len = this.length >>> 0; if (typeof fun != "function") throw new TypeError(); var thisp = arguments[1]; for (; i < len; i++) { if (i in this && fun.call(thisp, this[i], i, this)) return true; } return false; }; }