$('#email').autocomplete({

        delay:0,

        autoFocus:true,

        source:function(request,response){

            var hosts = ['qq.com','163.com','263.com','gmail.com','sina.com.cn'],

                term = request.term,//获取用户输入内容

                name = term,//邮箱的用户名

                host = '',//邮箱的域名

                ix = term.indexOf('@'),//@的位置

                result = [];//最终呈现的邮箱列表

            result.push(term);

            //当有@事重新分配用户名和域名

            if(ix > -1){

                name = term.slice(0,ix);

                host = term.slice(ix + 1);

            }

            if(name){

//                var findedHosts = (host ? findedHosts = $.grep(hosts,function(value,index){

//                        return value.indexOf(host) > -1;

//                    }) : hosts),

//                    findedResult = $.map(findedHosts, function(value,index) {

//                    return name + '@' + value;

//                });

                //如果用户已经输入@和后面的域名

                //那么就找到相关的域名提示，比如sfsdf@.1就提示sfsdf@.163.com

                //如果没输入都提示

                var findedHosts = [];

                if(host){

                    findedHosts = $.grep(hosts,function(value,index){

                        return value.indexOf(host) > -1;

                    });

                }else{

                    findedHosts = hosts;

                }

                var findedResult = $.map(findedHosts, function(value,index) {

                    return name + '@' + value;

                });

                result = result.concat(findedResult);

            }

            response(result);

        },

    });

$(function(){

    var arr = ['1234','jd','dang','12d3'];

    var a = $.grep(arr,function(value,index){

        return value.indexOf('d') > -1;

    });

    alert(a);

//    alert(a[1]);

//    var str = 'dangxingming';

//    alert(str.indexOf('k'));

});