js数组 删除某个元素
Array.prototype.indexOf = function(val) {
for (var i = 0; i < this.length; i++) {
if (this[i] == val) return i;
}
return -1;
};
Array.prototype.remove = function(val) {
var index = this.indexOf(val);
if (index > -1) {
this.splice(index, 1);
}
};
js数组是否含有某个元素
Array.prototype.contains = function ( needle ) {
for (i in this) {
if (this[i] == needle) return true;
}
return false;
}
判断value为undefined
if(typeof(value)=="undefined"){
alert("undefined");
}
cookie操作
//清除所有cookie
function clearAllCookie() {
var keys = document.cookie.match(/[^ =;]+(?=\=)/g);
if(keys) {
for(var i = keys.length; i--;)
document.cookie = keys[i] + '=0;expires=' + new Date(0).toUTCString();
}
}
