本文實例講述了JavaScript判斷數組是否包含指定元素的方法。分享給大家供大家參考。具體如下：
這段代碼通過prototype定義了數組方法，這樣就可以在任意數組調用contains方法
/**
* Array.prototype.[method name] allows you to define/overwrite an objects method
* needle is the item you are searching for
* this is a special variable that refers to "this" instance of an Array.
* returns true if needle is in the array, and false otherwise
*/
Array.prototype.contains = function ( needle ) {
for (i in this) {
if (this[i] == needle) return true;
}
return false;
}
用法：
// Now you can do things like:
var x = Array();
if (x.contains('foo')) {
// do something special
}
希望本文所述對大家的javascript程序設計有所幫助。