IE8下数组的indexOf失效的解决办法

//begin 解决ie8不支持数组的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;

};

}

//end

链接到js一开始的位置即可