autocomplete

html文件：

1 <input id="theInput"type="text" autocomplete="off">

js文件：

 1 this.initAutoComplete = function () {
        $("#theInput").autocomplete({　　　　　　　　　　　　　　　　　　　　　　　　//将$("#theInput")绑上autocomplete
            source: function (request, response) {　　　　　　　　　　　　　　　　 //source 参数
                $.ajax({
                    type: 'post',
                    url: "/CustomAccount/GetADUsers",
                    dataType: "json",
                    data: { mail: request.term,isall:false },                 //mail：request.term 传进去的是在#theInput中输入的值
                    success: function (data) {
                        response($.map(data, function (item) {
                            return {
                                displayname: item
                            };
                        }));
                    }
                });
            },
            select: function (event, ui) {　　　　　　　　                         //select参数
                $(this).val(ui.item.displayname);
                return false;
            },
            max: 10,
        }).each(function () {
            $(this).data("autocomplete")._renderItem = function (ul, item) {      //重写了autocomplete里面的_renderItem函数
                return $("<li>")
                    .data("item.autocomplete", item)
                    .append("<a data-type='autocomplete-item'>" + item.displayname + "</a>").attr('title', item.displayname)
                    .appendTo(ul);
            };
        });
    };

前台js调用这个initAutoComplete 函数，利用ajax在controller里面取值，controller

CustomAccountController里面的GetADUsers方法：

 [HttpPost]
 public ActionResult GetADUsers(string mail, Boolean isall)
{
  var results = this.systemUserService.FindADUsers(mail, isall);                           //return 一个list<String>，是根据传进来的mail值过滤的
  results.AddRange(this.systemUserService.FindADGroups(mail, isall).Select(g => g.Email));//在原来的results里加上另一个根据传进来的mail值过滤的的List<> 
6   results.Sort();                                                                          //排序  
7   return this.Json(results, JsonRequestBehavior.AllowGet);  
8 }

 附件jQuery UI Autocomplete 1.9.1：

/*!
 * jQuery UI Autocomplete 1.9.1
 * http://jqueryui.com
 *
 * Copyright 2012 jQuery Foundation and other contributors
 * Released under the MIT license.
 * http://jquery.org/license
 *
 * http://api.jqueryui.com/autocomplete/
 *
 * Depends:
 *    jquery.ui.core.js
 *    jquery.ui.widget.js
 *    jquery.ui.position.js
 *    jquery.ui.menu.js
 */
(function ($, undefined) {

    // used to prevent race conditions with remote data sources
    var requestIndex = 0;

    $.widget("ui.autocomplete", {
        version: "1.9.1",
        defaultElement: "<input>",
        options: {
            appendTo: "body",
            autoFocus: false,
            delay: 300,
            minLength: 1,
            position: {
                my: "left top",
                at: "left bottom",
                collision: "none"
            },
            source: null,            
            // callbacks
            change: null,
            close: null,
            focus: null,
            open: null,
            response: null,
            search: null,
            select: null,
             0,
            max: 10,

        },

        pending: 0,

        _create: function () {
            // Some browsers only repeat keydown events, not keypress events,
            // so we use the suppressKeyPress flag to determine if we've already
            // handled the keydown event. #7269
            // Unfortunately the code for & in keypress is the same as the up arrow,
            // so we use the suppressKeyPressRepeat flag to avoid handling keypress
            // events when we know the keydown event was used to modify the
            // search term. #7799
            var suppressKeyPress, suppressKeyPressRepeat, suppressInput;

            this.isMultiLine = this._isMultiLine();
            this.valueMethod = this.element[this.element.is("input,textarea") ? "val" : "text"];
            this.isNewMenu = true;

            this.element
                .addClass("ui-autocomplete-input")
                .attr("autocomplete", "off");

            this._on(this.element, {
                keydown: function (event) {
                    if (this.element.prop("readOnly")) {
                        suppressKeyPress = true;
                        suppressInput = true;
                        suppressKeyPressRepeat = true;
                        return;
                    }

                    suppressKeyPress = false;
                    suppressInput = false;
                    suppressKeyPressRepeat = false;
                    var keyCode = $.ui.keyCode;
                    switch (event.keyCode) {
                        case keyCode.PAGE_UP:
                            suppressKeyPress = true;
                            this._move("previousPage", event);
                            break;
                        case keyCode.PAGE_DOWN:
                            suppressKeyPress = true;
                            this._move("nextPage", event);
                            break;
                        case keyCode.UP:
                            suppressKeyPress = true;
                            this._keyEvent("previous", event);
                            break;
                        case keyCode.DOWN:
                            suppressKeyPress = true;
                            this._keyEvent("next", event);
                            break;
                        case keyCode.ENTER:
                        case keyCode.NUMPAD_ENTER:
                            // when menu is open and has focus
                            if (this.menu.active) {
                                // #6055 - Opera still allows the keypress to occur
                                // which causes forms to submit
                                suppressKeyPress = true;
                                event.preventDefault();
                                this.menu.select(event);
                            }
                            break;
                        case keyCode.TAB:
                            if (this.menu.active) {
                                this.menu.select(event);
                            }
                            break;
                        case keyCode.ESCAPE:
                            if (this.menu.element.is(":visible")) {
                                this._value(this.term);
                                this.close(event);
                                // Different browsers have different default behavior for escape
                                // Single press can mean undo or clear
                                // Double press in IE means clear the whole form
                                event.preventDefault();
                            }
                            break;
                        default:
                            suppressKeyPressRepeat = true;
                            // search timeout should be triggered before the input value is changed
                            this._searchTimeout(event);
                            break;
                    }
                },
                keypress: function (event) {
                    if (suppressKeyPress) {
                        suppressKeyPress = false;
                        event.preventDefault();
                        return;
                    }
                    if (suppressKeyPressRepeat) {
                        return;
                    }

                    // replicate some key handlers to allow them to repeat in Firefox and Opera
                    var keyCode = $.ui.keyCode;
                    switch (event.keyCode) {
                        case keyCode.PAGE_UP:
                            this._move("previousPage", event);
                            break;
                        case keyCode.PAGE_DOWN:
                            this._move("nextPage", event);
                            break;
                        case keyCode.UP:
                            this._keyEvent("previous", event);
                            break;
                        case keyCode.DOWN:
                            this._keyEvent("next", event);
                            break;
                    }
                },
                input: function (event) {
                    if (suppressInput) {
                        suppressInput = false;
                        event.preventDefault();
                        return;
                    }
                    this._searchTimeout(event);
                },
                focus: function () {
                    this.selectedItem = null;
                    this.previous = this._value();
                },
                blur: function (event) {
                    if (this.cancelBlur) {
                        delete this.cancelBlur;
                        return;
                    }

                    clearTimeout(this.searching);
                    this.close(event);
                    this._change(event);
                }
            });

            this._initSource();
            this.menu = $("<ul>")
                .addClass("ui-autocomplete")
                .appendTo(this.document.find(this.options.appendTo || "body")[0])
                .menu({
                    // custom key handling for now
                    input: $(),
                    // disable ARIA support, the live region takes care of that
                    role: null
                })
                .zIndex(this.element.zIndex() + 1)
                .hide()
                .data("menu");

            this._on(this.menu.element, {
                mousedown: function (event) {
                    // prevent moving focus out of the text field
                    event.preventDefault();

                    // IE doesn't prevent moving focus even with event.preventDefault()
                    // so we set a flag to know when we should ignore the blur event
                    this.cancelBlur = true;
                    this._delay(function () {
                        delete this.cancelBlur;
                    });

                    // clicking on the scrollbar causes focus to shift to the body
                    // but we can't detect a mouseup or a click immediately afterward
                    // so we have to track the next mousedown and close the menu if
                    // the user clicks somewhere outside of the autocomplete
                    var menuElement = this.menu.element[0];
                    if (!$(event.target).closest(".ui-menu-item").length) {
                        this._delay(function () {
                            var that = this;
                            this.document.one("mousedown", function (event) {
                                if (event.target !== that.element[0] &&
                                        event.target !== menuElement &&
                                        !$.contains(menuElement, event.target)) {
                                    that.close();
                                }
                            });
                        });
                    }
                },
                menufocus: function (event, ui) {
                    // #7024 - Prevent accidental activation of menu items in Firefox
                    if (this.isNewMenu) {
                        this.isNewMenu = false;
                        if (event.originalEvent && /^mouse/.test(event.originalEvent.type)) {
                            this.menu.blur();

                            this.document.one("mousemove", function () {
                                $(event.target).trigger(event.originalEvent);
                            });

                            return;
                        }
                    }

                    // back compat for _renderItem using item.autocomplete, via #7810
                    // TODO remove the fallback, see #8156
                    var item = ui.item.data("ui-autocomplete-item") || ui.item.data("item.autocomplete");
                    if (false !== this._trigger("focus", event, { item: item })) {
                        // use value to match what will end up in the input, if it was a key event
                        if (event.originalEvent && /^key/.test(event.originalEvent.type)) {
                            this._value(item.value);
                        }
                    } else {
                        // Normally the input is populated with the item's value as the
                        // menu is navigated, causing screen readers to notice a change and
                        // announce the item. Since the focus event was canceled, this doesn't
                        // happen, so we update the live region so that screen readers can
                        // still notice the change and announce it.
                        this.liveRegion.text(item.value);
                    }
                },
                menuselect: function (event, ui) {
                    // back compat for _renderItem using item.autocomplete, via #7810
                    // TODO remove the fallback, see #8156
                    var item = ui.item.data("ui-autocomplete-item") || ui.item.data("item.autocomplete"),
                        previous = this.previous;

                    // only trigger when focus was lost (click on menu)
                    if (this.element[0] !== this.document[0].activeElement) {
                        this.element.focus();
                        this.previous = previous;
                        // #6109 - IE triggers two focus events and the second
                        // is asynchronous, so we need to reset the previous
                        // term synchronously and asynchronously :-(
                        this._delay(function () {
                            this.previous = previous;
                            this.selectedItem = item;
                        });
                    }

                    if (false !== this._trigger("select", event, { item: item })) {
                        this._value(item.value);
                    }
                    // reset the term after the select event
                    // this allows custom select handling to work properly
                    this.term = this._value();

                    this.close(event);
                    this.selectedItem = item;
                }
            });

            this.liveRegion = $("<span>", {
                role: "status",
                "aria-live": "polite"
            })
                .addClass("ui-helper-hidden-accessible");
                //.insertAfter(this.element);

            if ($.fn.bgiframe) {
                this.menu.element.bgiframe();
            }

            // turning off autocomplete prevents the browser from remembering the
            // value when navigating through history, so we re-enable autocomplete
            // if the page is unloaded before the widget is destroyed. #7790
            this._on(this.window, {
                beforeunload: function () {
                    this.element.removeAttr("autocomplete");
                }
            });
        },//end _create

        _destroy: function () {
            clearTimeout(this.searching);
            this.element
                .removeClass("ui-autocomplete-input")
                .removeAttr("autocomplete");
            this.menu.element.remove();
            this.liveRegion.remove();
        },

        _setOption: function (key, value) {
            this._super(key, value);
            if (key === "source") {
                this._initSource();
            }
            if (key === "appendTo") {
                this.menu.element.appendTo(this.document.find(value || "body")[0]);
            }
            if (key === "disabled" && value && this.xhr) {
                this.xhr.abort();
            }
        },

        _isMultiLine: function () {
            // Textareas are always multi-line
            if (this.element.is("textarea")) {
                return true;
            }
            // Inputs are always single-line, even if inside a contentEditable element
            // IE also treats inputs as contentEditable
            if (this.element.is("input")) {
                return false;
            }
            // All other element types are determined by whether or not they're contentEditable
            return this.element.prop("isContentEditable");
        },

        _initSource: function () {
            var array, url,
                that = this;
            if ($.isArray(this.options.source)) {
                array = this.options.source;
                this.source = function (request, response) {
                    response($.ui.autocomplete.filter(array, request.term));
                };
            } else if (typeof this.options.source === "string") {
                url = this.options.source;
                this.source = function (request, response) {
                    if (that.xhr) {
                        that.xhr.abort();
                    }
                    that.xhr = $.ajax({
                        url: url,
                        data: request,
                        dataType: "json",
                        success: function (data) {
                            response(data);
                        },
                        error: function () {
                            response([]);
                        }
                    });
                };
            } else {
                this.source = this.options.source;
            }
        },

        _searchTimeout: function (event) {
            clearTimeout(this.searching);
            this.searching = this._delay(function () {
                // only search if the value has changed
                if (this.term !== this._value()) {
                    this.selectedItem = null;
                    this.search(null, event);
                }
            }, this.options.delay);
        },

        search: function (value, event) {
            value = value != null ? value : this._value();

            // always save the actual value, not the one passed as an argument
            this.term = this._value();

            if (value.length < this.options.minLength) {
                return this.close(event);
            }

            if (this._trigger("search", event) === false) {
                return;
            }

            return this._search(value);
        },

        _search: function (value) {
            this.pending++;
            this.element.addClass("ui-autocomplete-loading");
            this.cancelSearch = false;

            this.source({ term: value }, this._response());
        },

        _response: function () {
            var that = this,
                index = ++requestIndex;

            return function (content) {
                if (index === requestIndex) {
                    that.__response(content);
                }

                that.pending--;
                if (!that.pending) {
                    that.element.removeClass("ui-autocomplete-loading");
                }
            };
        },

        __response: function (content) {
            if (content) {
                content = this._normalize(content);
            }
            this._trigger("response", null, { content: content });
            //content && content.length && 
            if (!this.options.disabled && !this.cancelSearch) {
                this._suggest(content);
                this._trigger("open");
            } else {
                // use ._close() instead of .close() so we don't cancel future searches
                this._close();
            }
        },

        close: function (event) {
            this.cancelSearch = true;
            this._close(event);
        },

        _close: function (event) {
            if (this.menu.element.is(":visible")) {
                this.menu.element.hide();
                this.menu.blur();
                this.isNewMenu = true;
                this._trigger("close", event);
            }
        },

        _change: function (event) {
            if (this.previous !== this._value()) {
                this._trigger("change", event, { item: this.selectedItem });
            }
        },

        _normalize: function (items) {
            // assume all items have the right format when the first item is complete
            if (items.length && items[0].label && items[0].value) {
                return items;
            }
            return $.map(items, function (item) {
                if (typeof item === "string") {
                    return {
                        label: item,
                        value: item
                    };
                }
                return $.extend({
                    label: item.label || item.value,
                    value: item.value || item.label
                }, item);
            });
        },

        _suggest: function (items) {
            var ul = this.menu.element
                .empty()
                .zIndex(this.element.zIndex() + 1);
            this._renderMenu(ul, items);
            this.menu.refresh();
            // size and position menu
            ul.show();
            this._resizeMenu();
            ul.position($.extend({
                of: this.element
            }, this.options.position));

            if (this.options.autoFocus) {
                this.menu.next();
            }
        },

        _resizeMenu: function () {
            var that = this;
            var ul = this.menu.element;
            
            ul.outerWidth(                
                this.element.outerWidth()
            );
            
            
        },

        _limitNumberOfItems:function(available) {
            return this.options.max && this.options.max < available
            ? this.options.max
            : available;
        },

        _renderMenu: function (ul, items) {
            var that = this;
            var max = that._limitNumberOfItems(items.length);
            var num = 0;
            for (var i = 0; i < max; i++) {      
                    that._renderItemData(ul, items[i]);
                    num++;  
            }
            //$.each(items, function (index, item) {
            //    that._renderItemData(ul, item);
            //    num++;
            //});           
            var bottomlist = "<span class='autocomplete_bottom'>" +
                                "<span class='firstline'>Showing " +num+" Users</span>" +
                                "<span class='secondline' >"+
                                    "<span class='sprite-icon sprite-icon-info-16x16'></span>"+
                                    "<span class='autocomplete_bottom_txt'>Please type in more characters to narrow down the results.</span>" +
                                "</span></span>";
            ul.append(bottomlist);
            if (num == 0) {
                $('.secondline').hide();
                $('.firstline').text('No search results.');
            }
        },

        _renderItemData: function (ul, item) {
            return this._renderItem(ul, item).data("ui-autocomplete-item", item);
        },

        _renderItem: function (ul, item) {
            return $("<li>")
                .append($("<a>").text(item.label))
                .appendTo(ul);
        },

        _move: function (direction, event) {
            if (!this.menu.element.is(":visible")) {
                this.search(null, event);
                return;
            }
            if (this.menu.isFirstItem() && /^previous/.test(direction) ||
                    this.menu.isLastItem() && /^next/.test(direction)) {
                this._value(this.term);
                this.menu.blur();
                return;
            }
            this.menu[direction](event);
        },

        widget: function () {
            return this.menu.element;
        },

        _value: function () {
            return this.valueMethod.apply(this.element, arguments);
        },

        _keyEvent: function (keyEvent, event) {
            if (!this.isMultiLine || this.menu.element.is(":visible")) {
                this._move(keyEvent, event);

                // prevents moving cursor to beginning/end of the text field in some browsers
                event.preventDefault();
            }
        }
    });//end $.widget()


    $.extend($.ui.autocomplete, {
        escapeRegex: function (value) {
            return value.replace(/[\-\[\]{}()*+?.,\\\^$|#\s]/g, "\\$&");
        },
        filter: function (array, term) {
            var matcher = new RegExp($.ui.autocomplete.escapeRegex(term), "i");
            return $.grep(array, function (value) {
                return matcher.test(value.label || value.value || value);
            });
        }
    });

    // live region extension, adding a `messages` option
    // NOTE: This is an experimental API. We are still investigating
    // a full solution for string manipulation and internationalization.
    $.widget("ui.autocomplete", $.ui.autocomplete, {
        options: {
            messages: {
                noResults: "No search results.",
                results: function (amount) {
                    return amount + (amount > 1 ? " results are" : " result is") +
                        " available, use up and down arrow keys to navigate.";
                }
            }
        },

        __response: function (content) {
            var message;
            this._superApply(arguments);
            if (this.options.disabled || this.cancelSearch) {
                return;
            }
            if (content && content.length) {
                message = this.options.messages.results(content.length);
            } else {
                message = this.options.messages.noResults;
            }
            this.liveRegion.text(message).css('position','');
        }
    });


}(jQuery));