Question

jquery 判断数组里是否存在重复

Answer 1

// 方法一，正则判断
var ary = new Array("111","222","33","112","222");
alert(mm(ary))
// 验证重复元素，有重复返回true；否则返回false
function mm(a)
{
return /(\x0f[^\x0f]+)\x0f[\s\S]*\1/.test("\x0f"+a.join("\x0f\x0f") +"\x0f");
}

// 方法二，通过数组排序，比较临近元素，可指出重复的元素
var ary = newArray("111","22","33","111","22");
var nary = ary.sort();
for(var i = 0; i < nary.length - 1; i++)
{
if (nary[i] == nary[i+1])
{
alert("重复内容：" + nary[i]);
}
}

// 方法三，通过字符串查找
var ary = newArray("111","22","33","111","22");
var s = ary.join(",") +",";
for(var i = 0; i < ary.length; i++)
{
if(s.replace(ary[i] + ",", "").indexOf(ary[i] +",") > -1)
{
alert("重复内容：" + ary[i]);
}
}

// 方法四，通过哈希
var ary = newArray("111","22","33","111","22");
alert(isRepeat(ary));
// 验证重复元素，有重复返回true；否则返回false
function isRepeat(arr) {
var hash = {};
for(var i in arr) {
if(hash[arr[i]])
{
return true;
}
// 不存在该元素，则赋值为true，可以赋任意值，相应的修改if判断条件即可
hash[arr[i]] = true;
}
return false;
}

Answer 2

function Each(list, fun){ 
for (var i = 0, len = list.length; i < len; i++) { fun(list[i], i); } 
}; 
var arr = [1,2,3,4,1,3] 
var t 
Each(arr.sort(), function(o,i){ 
if(i>0 && o == t){ alert("相同的:" + o); } 
alert(t) 
t = o; 
})