下拉搜索框(兼容ie8)

github上找到的然后自己稍微改了一下，省的后面要找找不到 地址

// 搜索下拉框
var flag = true
;
(function(root, factory) {
    if (typeof exports === 'object') { //umd
        module.exports =factory($);
    } else {
        root.AutoSearch = factory(window.Zepto || window.jQuery || $);
    }
})(this, function($) {
    function AutoSearch() {}
    AutoSearch.prototype = {
        init: function(settings) {
            var rnd = Math.random().toString().replace('.', '');
            this.id = 'autosearch_' + rnd;
            this.settings = $.extend({
                mutil: false,
                autoHide:true,
                isdel:false,
                allDelText:'清除全部记录'
            }, settings);
            this.input = $(this.settings.input);
            this.min = this.settings.min || 1;
            this.data = this.settings.data;
            this.valueObj = $(this.settings.valueObj || this.settings.input); //赋值项
            this.valueName = this.settings.valueName || 'name';; //赋值项
            this.valueNames = this.settings.valueNames || 'name';; //赋值项
            this.target = $(this.settings.target || this.settings.input); //显示框
            this.filterColumn = this.settings.filterColumn || ['name'];
            this.column = this.settings.column || ['name'];
            this.timer = null;
            this.content = null;
            this.mutilValueArr = [];
            this.mutilTextArr = [];
            this.createContent();
            this.bindEvent();
        },
        bindEvent: function() {
            var _this = this;
            this.target.click(function(e) {
                if(!flag) {
                    return
                }
                flag = false
                setTimeout(function() {
                    flag = true
                },1000)
                if (_this.settings.autoShow) {
                    _this.search();
                    
                }
                return false;
            });
            this.input.on('focus', function(e) {
                var input = $(this);
                // _this.timer && clearInterval(_this.timer);
                // _this.timer = setInterval(function() {
                //     if (input.data('old') != input.val()) {
                //         _this.search();
                //         input.data('old', input.val());
                //     }
                // }, 25);
                _this.settings.focusCallback && _this.settings.focusCallback.call(_this, _this.input);
            }).on('keyup', function(e) {
                e.stopPropagation(e)
                var input = $(this);
                if (input.data('old') != input.val() && e.keyCode != 13) {
                    _this.search();
                    input.data('old', input.val());
                }
                //console.log(e.keyCode)
            }).on('blur', function(e) {
                e.stopPropagation()
                // if(_this.settings.autoHide){
                //     if (_this.timer) {
                //         clearInterval(_this.timer);
                //     }
                //     var input = $(this);
                //     setTimeout(function() {
                //         _this.hide();
                //         if (input.attr('data-text') != input.val() && !_this.settings.mutil) {
                //             _this.input.val('');
                //             _this.input.data('old','')
                //             _this.valueObj.val('');
                //             _this.input.attr('data-text','');
                //             _this.input.attr('data-value','');
                //             _this.settings.resetCallback && _this.settings.resetCallback.call(_this, _this.input);
                //         }
                //     }, 500)
                // }
                // _this.settings.blurCallback && _this.settings.blurCallback.call(_this, _this.input);
            }).on('keyup', function(e) {
                e.preventDefault()
                e.stopPropagation()
                switch (e.keyCode) {
                    case 40:
                        {
                            //down
                            var i = $('.item.current', _this.content).index();
                            i++;
                            i = Math.min($('.item', _this.content).size() - 1, i);
                            var current = $('.item.current', _this.content);
                            $('.item', _this.content).removeClass('current').eq(i).addClass('current');
                            if (current.size()) {
                                var pos = $('.item.current', _this.content).position();
                                var ch = current.outerHeight();
                                if (pos.top + ch > $(_this.content).height()) {
                                    var st = $(_this.content).scrollTop();
                                    st += ch;
                                    $(_this.content).scrollTop(st);
                                }
                            }
                            break;
                        }
                    case 38:
                        {
                            //up
                            var i = $('.item.current', _this.content).index();
                            i--;
                            i = Math.max(0, i);
                            $('.item', _this.content).removeClass('current').eq(i).addClass('current');
                            var current = $('.item.current', _this.content);
                            if (current.size()) {
                                var pos = $('.item.current', _this.content).position();
                                var ch = current.outerHeight();
                                var st = $(_this.content).scrollTop();
                                if (pos.top <= 0) {
                                    st -= ch;
                                    $(_this.content).scrollTop(Math.max(st, 0));
                                }
                            }
                            break;
                        }
                    case 13:
                        {
                            //enter
                            $('.item.current', _this.content).trigger('click');
                            setTimeout(function() {
                                _this.hide();
                            }, 50)
                            _this.settings.enterCallback&&_this.settings.enterCallback.call(_this,this);
                            break;
                        }
                }
            }).on('keydown', function(e) {
                e.stopPropagation()
                if (e.keyCode == 13) {
                    e.preventDefault();
                }
            });
            this.content.on('click', '.item', function(e) {
                e.stopPropagation()
                var data = $(this).data('data');
                var text = $('span',this).text();
                if (_this.settings.mutil == true) {
                    _this.mutilTextArr.push(text);
                    _this.mutilValueArr.push(data[_this.valueName]);
                    _this.input.val(_this.mutilTextArr.join(',') + ',');
                    _this.valueObj.val(_this.mutilValueArr.join(',') + ',');
                    _this.input.attr('data-value', _this.input.attr('data-value'));
                    _this.input.attr('data-text', _this.mutilTextArr.join(',') + ',');
                } else {
                    _this.input.val(text);
                    _this.valueObj.val(data[_this.valueName]);
                    _this.input.attr('data-value', data[_this.valueNames]);
                    if (_this.settings.valueObj) {
                        _this.input.attr('data-text', text);
                    } else {
                        _this.input.attr('data-text', data[_this.valueName]);
                    }
                }
                _this.settings.callback && _this.settings.callback.call(_this, data);
                _this.hide();
            }).on('mouseover', '.item', function(e) {
                e.stopPropagation()
                $(this).addClass('current').siblings().removeClass('current');
            })
            $(document).click(function(e) {
                e.stopPropagation()
                _this.hide();
            });
            this.content.on('click', '.ats_del', function(e) {
                e.stopPropagation()
                //删除
                var item = $(this).closest('.item');
                _this.settings.delCallback && _this.settings.delCallback.call(_this,item);
                item.remove();
                return false;
            });
        },
        createContent: function() {
            if ($('#' + this.id).size() == 0) {
                this.content = $('<div id="' + this.id + '" class="ui-autosearch-content"/>');
                this.content.hide();
                $('body').append(this.content);
            }
        },
        show: function() {
            var _this = this;
            _this.content.show();
            _this.content.css({
                position: 'absolute',
                zIndex: _this.settings.zIndex || 999,
                 _this.input.outerWidth()
            });
            _this.setPostion();
            _this.postimer = setInterval(function() {
                _this.setPostion();
            }, 20);
            _this.settings.showCallback && _this.settings.showCallback.call(_this, _this.input, _this.content);
        },
        hide: function() {
            this.postimer && clearInterval(this.postimer)
            this.content.hide()
        },
        search: function() {
            var _this = this;
            var value = _this.input.val().split(',').pop();
            var len = _this.getByteLen(value);
            if (len >= _this.min || _this.settings.autoShow) {
                if (typeof _this.data === "function") {
                    //ajax
                    _this.getData();
                } else {
                    var data = _this.filter(_this.data);
                    _this.format(data);
                    if(data.length){
                        _this.show();
                    }else{
                        _this.hide()
                    }
                }
            } else {
                _this.hide();
            }
        },
        getData: function() {
            var _this = this;
            this.settings.data(function(data) {
                _this.format(data);
                _this.show();
            });
        },
        format: function(data) {
            this.content.html('');
            if (data) {
                for (var i = 0, l = data.length; i < l; i++) {
                    
                    var item = data[i];
                    var row = $();
                    if (this.settings.format) {
                        row = $(this.settings.format.call(this, item));
                    } else {
                        var name = '';
                        for (var j = 0, len = this.column.length; j < len; j++) {
                            name += '<span class="' + this.column[j] + '">' + item[this.column[j]] + '</span>';
                        };
                        if(this.settings.isdel){
                            row = $('<div class="item">' + name + '<i class="ats_del">✖</i></div>');
                        }else{
                            row = $('<div class="item">' + name + '</div>');
                        }
                    }
                    row.data('data', item)
                    this.content.append(row);
                };
                if(this.settings.isdel){
                    var delrow = $('<div class="item">'+this.settings.allDelText+'</div>');
                    delrow.click(function(){
                        $(this).siblings('.item').find('.ats_del').trigger('click');
                        return false;
                    })
                    this.content.append(delrow);
                }
            }
        },
        filter: function(data) {
            var _this = this;
            var value = _this.input.val().split(',').pop();
            var newData = [];
            for (var i = 0, l = data.length; i < l; i++) {
                var item = data[i];
                for (var j = 0, len = _this.filterColumn.length; j < len; j++) {
                    var v = item[_this.filterColumn[j]]
                    if (v.toString().indexOf(value) != -1) {
                        newData.push(item);
                    }
                }
            }
            return newData;
        },
        setPostion: function() {
            var _this = this;
            var offset = _this.input.offset();
            _this.content.css({
                top: offset.top + _this.input.outerHeight(),
                // top: offset.top - 206,
                left: offset.left
            });
        },

        getByteLen:function(val) {
            var len = 0;
            for (var i = 0; i < val.length; i++) {
                var patt = new RegExp(/[^x00-xff]/ig);
                var a = val[i];
                if (patt.test(a))
                {
                    len += 2;
                }
                else
                {
                    len += 1;
                }
            }
            return len;
        }
    }
    return AutoSearch;
});