带有显示结果的 jquery 下拉列表的搜索栏

Search bar with jquery dropdown showing results

当用户在搜索栏中输入内容时,我希望在您单击页面时将 link 下方的结果显示在页面上,而不是用您单击的内容填充搜索栏。我是 Jquery 的新手,我在网上找到了这个教程,但它并不完全符合我的要求。

Index.php(只显示部分头部和body)

<script>
$(document).ready(function(){
 $("#tag").autocomplete("autocomplete.php", {
        selectFirst: true
    });
});
</script>
</head>

<body>
    <label>Tag:</label>
    <input name="tag" type="text" id="tag" size="20" style="width:541px; height:23px; font-size:16px; text-indent:5px;" placeholder="Search foods, shopping lists, meal plans and recipes" />
</body>

autocomplete.php(即使使用 和 标签我也无法实现 linking 到另一个页面。)

<?php
$q=$_GET['q'];
$my_data=mysql_real_escape_string($q);
include ("connect.php");
$sql="SELECT id, name, description, foodgroup FROM foods WHERE name LIKE '%$my_data%' ORDER BY name";
$result = mysql_query($sql);

if($result) {
    while($row=mysql_fetch_array($result)) {
        print "<a href='food.php?foodGroup=" . $row['foodgroup'] . "&name=" . $row['name'] . "&desc=" . $row['description'] . "&foodID=" . $row['id'] . "'><div id='resultContainerDiv'><span id='resultText'>" . $row['name'] . " - " . $row['description'] . "</span></div></a>\n";
    }
}
?>

最后,jquery.autocomplete.js

/*  * jQuery Autocomplete plugin 1.1  *  * Copyright (c) 2009 Jörn Zaefferer  *  * Dual licensed under the MIT and GPL licenses:  *   http://www.opensource.org/licenses/mit-license.php  *   http://www.gnu.org/licenses/gpl.html  *  * Revision: $Id: jquery.autocomplete.js 15 2009-08-22 10:30:27Z joern.zaefferer $  */

;(function($) {      $.fn.extend({  autocomplete: function(urlOrData, options) {        var isUrl = typeof urlOrData == "string";       options = $.extend({}, $.Autocompleter.defaults, {          url: isUrl ? urlOrData : null,          data: isUrl ? null : urlOrData,             delay: isUrl ? $.Autocompleter.defaults.delay : 10,             max: options && !options.scroll ? 10 : 150      }, options);
                // if highlight is set to false, replace it with a do-nothing function      options.highlight = options.highlight || function(value) { return value; };
                // if the formatMatch option is not specified, then use formatItem for backwards compatibility      options.formatMatch = options.formatMatch || options.formatItem;
                return this.each(function() {           new $.Autocompleter(this, options);         });     },  result: function(handler) {         return this.bind("result", handler);    },  search: function(handler) {         return this.trigger("search", [handler]);   },  flushCache: function() {        return this.trigger("flushCache");  },  setOptions: function(options){      return this.trigger("setOptions", [options]);   },  unautocomplete: function() {        return this.trigger("unautocomplete");  } });

$.Autocompleter = function(input, options) {

    var KEY = {         UP: 38,         DOWN: 40,       DEL: 46,        TAB: 9,         RETURN: 13,         ESC: 27,        COMMA: 188,         PAGEUP: 33,         PAGEDOWN: 34,       BACKSPACE: 8    };

    // Create $ object for input element    var $input = $(input).attr("autocomplete", "off").addClass(options.inputClass);

    var timeout;    var previousValue = "";     var cache = $.Autocompleter.Cache(options);     var hasFocus = 0;   var lastKeyPressCode;   var config = {      mouseDownOnSelect: false    };  var select = $.Autocompleter.Select(options, input, selectCurrent, config);         var blockSubmit;        // prevent form submit in opera when selecting with return key  $.browser.opera && $(input.form).bind("submit.autocomplete", function() {       if (blockSubmit) {          blockSubmit = false;            return false;       }   });         // only opera doesn't trigger keydown multiple times while pressed, others don't work with keypress at all  $input.bind(($.browser.opera ? "keypress" : "keydown") + ".autocomplete", function(event) {         // a keypress means the input has focus         // avoids issue where input had focus before the autocomplete was applied       hasFocus = 1;       // track last key pressed       lastKeyPressCode = event.keyCode;       switch(event.keyCode) {
                    case KEY.UP:
                event.preventDefault();
                if ( select.visible() ) {
                    select.prev();
                } else {
                    onChange(0, true);
                }
                break;
                            case KEY.DOWN:
                event.preventDefault();
                if ( select.visible() ) {
                    select.next();
                } else {
                    onChange(0, true);
                }
                break;
                            case KEY.PAGEUP:
                event.preventDefault();
                if ( select.visible() ) {
                    select.pageUp();
                } else {
                    onChange(0, true);
                }
                break;
                            case KEY.PAGEDOWN:
                event.preventDefault();
                if ( select.visible() ) {
                    select.pageDown();
                } else {
                    onChange(0, true);
                }
                break;
                        // matches also semicolon           case options.multiple && $.trim(options.multipleSeparator) == "," && KEY.COMMA:             case KEY.TAB:           case KEY.RETURN:
                if( selectCurrent() ) {
                    // stop default to prevent a form submit, Opera needs special handling
                    event.preventDefault();
                    blockSubmit = true;
                    return false;
                }
                break;
                            case KEY.ESC:
                select.hide();
                break;
                            default:
                clearTimeout(timeout);
                timeout = setTimeout(onChange, options.delay);
                break;      }   }).focus(function(){        // track whether the field has focus, we shouldn't process any      // results if the field no longer has focus         hasFocus++;     }).blur(function() {        hasFocus = 0;       if (!config.mouseDownOnSelect) {            hideResults();      }   }).click(function() {       // show select when clicking in a focused field         if ( hasFocus++ > 1 && !select.visible() ) {            onChange(0, true);      }   }).bind("search", function() {      // TODO why not just specifying both arguments?         var fn = (arguments.length > 1) ? arguments[1] : null;      function findValueCallback(q, data) {           var result;             if( data && data.length ) {
                for (var i=0; i < data.length; i++) {
                    if( data[i].result.toLowerCase() == q.toLowerCase() ) {
                        result = data[i];
                        break;
                    }
                }           }           if( typeof fn == "function" ) fn(result);           else $input.trigger("result", result && [result.data, result.value]);       }       $.each(trimWords($input.val()), function(i, value) {            request(value, findValueCallback, findValueCallback);       });     }).bind("flushCache", function() {      cache.flush();  }).bind("setOptions", function() {      $.extend(options, arguments[1]);        // if we've updated the data, repopulate        if ( "data" in arguments[1] )           cache.populate();   }).bind("unautocomplete", function() {      select.unbind();        $input.unbind();        $(input.form).unbind(".autocomplete");  });
            function selectCurrent() {      var selected = select.selected();       if( !selected )             return false;
                var v = selected.result;        previousValue = v;
                if ( options.multiple ) {           var words = trimWords($input.val());            if ( words.length > 1 ) {
                var seperator = options.multipleSeparator.length;
                var cursorAt = $(input).selection().start;
                var wordAt, progress = 0;
                $.each(words, function(i, word) {
                    progress += word.length;
                    if (cursorAt <= progress) {
                        wordAt = i;
                        return false;
                    }
                    progress += seperator;
                });
                words[wordAt] = v;
                // TODO this should set the cursor to the right position, but it gets overriden somewhere
                //$.Autocompleter.Selection(input, progress + seperator, progress + seperator);
                v = words.join( options.multipleSeparator );            }           v += options.multipleSeparator;         }
                $input.val(v);      hideResultsNow();       $input.trigger("result", [selected.data, selected.value]);      return true;    }       function onChange(crap, skipPrevCheck) {        if( lastKeyPressCode == KEY.DEL ) {             select.hide();          return;         }
                var currentValue = $input.val();
                if ( !skipPrevCheck && currentValue == previousValue )          return;
                previousValue = currentValue;
                currentValue = lastWord(currentValue);      if ( currentValue.length >= options.minChars) {             $input.addClass(options.loadingClass);          if (!options.matchCase)
                currentValue = currentValue.toLowerCase();          request(currentValue, receiveData, hideResultsNow);         } else {            stopLoading();          select.hide();      }   };      function trimWords(value) {         if (!value)             return [""];        if (!options.multiple)          return [$.trim(value)];         return $.map(value.split(options.multipleSeparator), function(word) {           return $.trim(value).length ? $.trim(word) : null;      });     }       function lastWord(value) {      if ( !options.multiple )            return value;       var words = trimWords(value);       if (words.length == 1)              return words[0];        var cursorAt = $(input).selection().start;      if (cursorAt == value.length) {             words = trimWords(value)        } else {            words = trimWords(value.replace(value.substring(cursorAt), ""));        }       return words[words.length - 1];     }       // fills in the input box w/the first match (assumed to be the best match)  // q: the term entered  // sValue: the first matching result    function autoFill(q, sValue){       // autofill in the complete box w/the first match as long as the user hasn't entered in more data       // if the last user key pressed was backspace, don't autofill       if( options.autoFill && (lastWord($input.val()).toLowerCase() == q.toLowerCase()) && lastKeyPressCode != KEY.BACKSPACE ) {          // fill in the value (keep the case the user has typed)             $input.val($input.val() + sValue.substring(lastWord(previousValue).length));            // select the portion of the value not typed by the user (so the next character will erase)             $(input).selection(previousValue.length, previousValue.length + sValue.length);         }   };

    function hideResults() {        clearTimeout(timeout);      timeout = setTimeout(hideResultsNow, 200);  };

    function hideResultsNow() {         var wasVisible = select.visible();      select.hide();      clearTimeout(timeout);      stopLoading();      if (options.mustMatch) {            // call search and run callback             $input.search(
                function (result){
                    // if no value found, clear the input box
                    if( !result ) {
                        if (options.multiple) {
                            var words = trimWords($input.val()).slice(0, -1);
                            $input.val( words.join(options.multipleSeparator) + (words.length ? options.multipleSeparator : "") );
                        }
                        else {
                            $input.val( "" );
                            $input.trigger("result", null);
                        }
                    }
                }           );      }   };

    function receiveData(q, data) {         if ( data && data.length && hasFocus ) {            stopLoading();          select.display(data, q);            autoFill(q, data[0].value);             select.show();      } else {            hideResultsNow();       }   };

    function request(term, success, failure) {      if (!options.matchCase)             term = term.toLowerCase();      var data = cache.load(term);        // recieve the cached data      if (data && data.length) {          success(term, data);        // if an AJAX url has been supplied, try loading the data now       } else if( (typeof options.url == "string") && (options.url.length > 0) ){
                        var extraParams = {
                timestamp: +new Date()          };          $.each(options.extraParams, function(key, param) {
                extraParams[key] = typeof param == "function" ? param() : param;            });
                        $.ajax({
                // try to leverage ajaxQueue plugin to abort previous requests
                mode: "abort",
                // limit abortion to this input
                port: "autocomplete" + input.name,
                dataType: options.dataType,
                url: options.url,
                data: $.extend({
                    q: lastWord(term),
                    limit: options.max
                }, extraParams),
                success: function(data) {
                    var parsed = options.parse && options.parse(data) || parse(data);
                    cache.add(term, parsed);
                    success(term, parsed);
                }           });         } else {            // if we have a failure, we need to empty the list -- this prevents the the [TAB] key from selecting the last successful match          select.emptyList();             failure(term);      }   };      function parse(data) {      var parsed = [];        var rows = data.split("\n");        for (var i=0; i < rows.length; i++) {           var row = $.trim(rows[i]);          if (row) {
                row = row.split("|");
                parsed[parsed.length] = {
                    data: row,
                    value: row[0],
                    result: options.formatResult && options.formatResult(row, row[0]) || row[0]
                };          }       }       return parsed;  };

    function stopLoading() {        $input.removeClass(options.loadingClass);   };

};

$.Autocompleter.defaults = {    inputClass: "ac_input",     resultsClass: "ac_results",     loadingClass: "ac_loading",     minChars: 1,    delay: 400,     matchCase: false,   matchSubset: true,  matchContains: false,   cacheLength: 10,    max: 100,   mustMatch: false,   extraParams: {},    selectFirst: true,  formatItem: function(row) { return row[0]; },   formatMatch: null,  autoFill: false,    width: 0,   multiple: false,    multipleSeparator: ", ",    highlight: function(value, term) {      return value.replace(new RegExp("(?![^&;]+;)(?!<[^<>]*)(" + term.replace(/([\^$\(\)\[\]\{\}\*\.\+\?\|\])/gi, "\") + ")(?![^<>]*>)(?![^&;]+;)", "gi"), "<strong></strong>");  },
    scroll: true,
    scrollHeight: 180 };

$.Autocompleter.Cache = function(options) {

    var data = {};  var length = 0;         function matchSubset(s, sub) {      if (!options.matchCase)             s = s.toLowerCase();        var i = s.indexOf(sub);         if (options.matchContains == "word"){           i = s.toLowerCase().search("\b" + sub.toLowerCase());      }       if (i == -1) return false;      return i == 0 || options.matchContains;     };      function add(q, value) {        if (length > options.cacheLength){          flush();        }       if (!data[q]){              length++;       }       data[q] = value;    }       function populate(){        if( !options.data ) return false;       // track the matches        var stMatchSets = {},           nullData = 0;

        // no url was specified, we need to adjust the cache length to make sure it fits the local data store       if( !options.url ) options.cacheLength = 1;
                // track all options for minChars = 0       stMatchSets[""] = [];
                // loop through the array and create a lookup structure         for ( var i = 0, ol = options.data.length; i < ol; i++ ) {          var rawValue = options.data[i];             // if rawValue is a string, make an array otherwise just reference the array            rawValue = (typeof rawValue == "string") ? [rawValue] : rawValue;
                        var value = options.formatMatch(rawValue, i+1, options.data.length);            if ( value === false )
                continue;
                            var firstChar = value.charAt(0).toLowerCase();          // if no lookup array for this character exists, look it up now             if( !stMatchSets[firstChar] ) 
                stMatchSets[firstChar] = [];

            // if the match is a string             var row = {
                value: value,
                data: rawValue,
                result: options.formatResult && options.formatResult(rawValue) || value             };
                        // push the current match into the set list             stMatchSets[firstChar].push(row);

            // keep track of minChars zero items            if ( nullData++ < options.max ) {
                stMatchSets[""].push(row);          }       };

        // add the data items to the cache      $.each(stMatchSets, function(i, value) {            // increase the cache size          options.cacheLength++;          // add to the cache             add(i, value);      });     }       // populate any existing data   setTimeout(populate, 25);       function flush(){       data = {};      length = 0;     }       return {        flush: flush,       add: add,       populate: populate,         load: function(q) {             if (!options.cacheLength || !length)
                return null;            /* 
             * if dealing w/local data and matchContains than we must make sure
             * to loop through all the data collections looking for matches
             */             if( !options.url && options.matchContains ){
                // track all matches
                var csub = [];
                // loop through all the data grids for matches
                for( var k in data ){
                    // don't search through the stMatchSets[""] (minChars: 0) cache
                    // this prevents duplicates
                    if( k.length > 0 ){
                        var c = data[k];
                        $.each(c, function(i, x) {
                            // if we've got a match, add it to the array
                            if (matchSubset(x.value, q)) {
                                csub.push(x);
                            }
                        });
                    }
                }               
                return csub;            } else              // if the exact item exists, use it             if (data[q]){
                return data[q];             } else          if (options.matchSubset) {
                for (var i = q.length - 1; i >= options.minChars; i--) {
                    var c = data[q.substr(0, i)];
                    if (c) {
                        var csub = [];
                        $.each(c, function(i, x) {
                            if (matchSubset(x.value, q)) {
                                csub[csub.length] = x;
                            }
                        });
                        return csub;
                    }
                }           }           return null;        }   }; };

$.Autocompleter.Select = function (options, input, select, config) {    var CLASSES = {         ACTIVE: "ac_over"   };      var listItems,      active =
-1,         data,       term = "",      needsInit = true,       element,        list;       // Create results   function init() {       if (!needsInit)             return;         element = $("<div/>")       .hide()         .addClass(options.resultsClass)         .css("position", "absolute")        .appendTo(document.body);
            list = $("<ul/>").appendTo(element).mouseover( function(event) {            if(target(event).nodeName && target(event).nodeName.toUpperCase()
== 'LI') {
                active = $("li", list).removeClass(CLASSES.ACTIVE).index(target(event));
                $(target(event)).addClass(CLASSES.ACTIVE);            
            }       }).click(function(event) {          $(target(event)).addClass(CLASSES.ACTIVE);          select();           // TODO provide option to avoid setting focus again after selection? useful for cleanup-on-focus            input.focus();          return false;       }).mousedown(function() {           config.mouseDownOnSelect = true;        }).mouseup(function() {             config.mouseDownOnSelect = false;       });
                if( options.width > 0 )             element.css("width", options.width);
                    needsInit = false;  }       function target(event) {        var element = event.target;         while(element && element.tagName != "LI")           element = element.parentNode;       // more fun with IE, sometimes event.target is empty, just ignore it then       if(!element)            return [];      return element;     }

    function moveSelect(step) {         listItems.slice(active, active + 1).removeClass(CLASSES.ACTIVE);        movePosition(step);
        var activeItem = listItems.slice(active, active + 1).addClass(CLASSES.ACTIVE);
        if(options.scroll) {
            var offset = 0;
            listItems.slice(0, active).each(function() {
                offset += this.offsetHeight;            });
            if((offset + activeItem[0].offsetHeight - list.scrollTop()) > list[0].clientHeight) {
                list.scrollTop(offset + activeItem[0].offsetHeight - list.innerHeight());
            } else if(offset < list.scrollTop()) {
                list.scrollTop(offset);
            }
        }   };      function movePosition(step) {       active += step;         if (active < 0) {           active = listItems.size() - 1;      } else if (active
>= listItems.size()) {          active = 0;         }   }       function limitNumberOfItems(available) {        return options.max && options.max < available           ? options.max           : available;    }       function fillList() {       list.empty();       var max = limitNumberOfItems(data.length);      for (var i=0; i < max; i++) {           if (!data[i])
                continue;           var formatted = options.formatItem(data[i].data, i+1, max, data[i].value, term);            if ( formatted === false )
                continue;           var li = $("<li/>").html( options.highlight(formatted, term) ).addClass(i%2 == 0 ? "ac_even" : "ac_odd").appendTo(list)[0];             $.data(li, "ac_data", data[i]);         }       listItems = list.find("li");        if ( options.selectFirst ) {            listItems.slice(0, 1).addClass(CLASSES.ACTIVE);             active = 0;         }       // apply bgiframe if available      if ( $.fn.bgiframe )            list.bgiframe();    }       return {        display: function(d, q) {           init();             data = d;           term = q;           fillList();         },      next: function() {          moveSelect(1);      },      prev: function() {          moveSelect(-1);         },      pageUp: function() {            if (active != 0 && active - 8 < 0) {
                moveSelect( -active );          } else {
                moveSelect(-8);             }       },      pageDown: function() {          if (active != listItems.size() - 1 && active + 8 > listItems.size()) {
                moveSelect( listItems.size() - 1 - active );            } else {
                moveSelect(8);          }       },      hide: function() {          element && element.hide();          listItems && listItems.removeClass(CLASSES.ACTIVE);             active = -1;        },      visible : function() {          return element && element.is(":visible");       },      current: function() {           return this.visible() && (listItems.filter("." + CLASSES.ACTIVE)[0] || options.selectFirst && listItems[0]);        },      show: function() {          var offset = $(input).offset();             element.css({
                width: typeof options.width == "string" || options.width > 0 ? options.width : $(input).width(),
                top: offset.top + input.offsetHeight,
                left: offset.left           }).show();
            if(options.scroll) {
                list.scrollTop(0);
                list.css({
                    maxHeight: options.scrollHeight,
                    overflow: 'auto'
                });

                if($.browser.msie && typeof document.body.style.maxHeight === "undefined") {
                    var listHeight = 0;
                    listItems.each(function() {
                        listHeight += this.offsetHeight;
                    });
                    var scrollbarsVisible = listHeight > options.scrollHeight;
                    list.css('height', scrollbarsVisible ? options.scrollHeight : listHeight );
                    if (!scrollbarsVisible) {
                        // IE doesn't recalculate width when scrollbar disappears
                        listItems.width( list.width() - parseInt(listItems.css("padding-left")) - parseInt(listItems.css("padding-right")) );
                    }
                }

            }       },      selected: function() {          var selected = listItems && listItems.filter("." + CLASSES.ACTIVE).removeClass(CLASSES.ACTIVE);             return selected && selected.length && $.data(selected[0], "ac_data");       },      emptyList: function (){             list && list.empty();       },      unbind: function() {            element && element.remove();        }   }; };

$.fn.selection = function(start, end) {     if (start !== undefined) {      return this.each(function() {           if( this.createTextRange ){
                var selRange = this.createTextRange();
                if (end === undefined || start == end) {
                    selRange.move("character", start);
                    selRange.select();
                } else {
                    selRange.collapse(true);
                    selRange.moveStart("character", start);
                    selRange.moveEnd("character", end);
                    selRange.select();
                }           } else if( this.setSelectionRange ){
                this.setSelectionRange(start, end);             } else if( this.selectionStart ){
                this.selectionStart = start;
                this.selectionEnd = end;            }       });     }   var field = this[0];    if ( field.createTextRange ) {      var range = document.selection.createRange(),           orig = field.value,             teststring
= "<->",            textLength = range.text.length;         range.text = teststring;        var caretAt = field.value.indexOf(teststring);      field.value = orig;         this.selection(caretAt, caretAt + textLength);      return {            start: caretAt,             end: caretAt + textLength       }   } else if( field.selectionStart !== undefined ){        return {            start: field.selectionStart,            end: field.selectionEnd         }   } };

})(jQuery);

谢谢,

瑞安

您在搜索脚本中遇到错误:

<?php
$q=$_GET['q'];
$my_data=mysql_real_escape_string($q);
include ("connect.php");
如果还没有数据库连接,

mysql_real_escape_string 将 return false(相当于空字符串),因此您实际上是在清空搜索字符串。

你需要改变它:

<?php
$q=$_GET['q'];
include ("connect.php");
$my_data=mysql_real_escape_string($q);

您还应该在数据库调用中添加错误处理,并尽可能转移到 PDO 或 mysqli,因为 mysql_* 函数已被弃用。