如何允许datepicker在JQuery中选择未来的日期？

Question

我需要一个针对我们项目的日期选择器，同时在线查看..我找到了一个。但是，它禁用以允许将来的日期。我试着查看代码，但我无法完全理解它。我是JQuery的新手。

这是代码（很长很抱歉）：

<script>
        $.datepicker._defaults.isDateSelector = false; 
        $.datepicker._defaults.onAfterUpdate = null;
        $.datepicker._defaults.base_update = $.datepicker._updateDatepicker;
        $.datepicker._defaults.base_generate = $.datepicker._generateHTML;

        function DateRange(options) {
            if (!options.startField) throw "Missing Required Start Field!";
            if (!options.endField) throw "Missing Required End Field!";

            var isDateSelector = true;

            var cur = -1,prv = -1, cnt = 0;   
            var df = options.dateFormat ? options.dateFormat:'mm/dd/yy';
            var RangeType = {ID:'rangetype',BOTH:0,START:1,END:2};
            var sData = {input:$(options.startField),div:$(document.createElement("DIV"))};
            var eData = {input:null,div:null};

            /*
             * Overloading JQuery DatePicker to add functionality - This should use WidgetFactory!
             */
             $.datepicker._updateDatepicker = function (inst) {
                  var base = this._get(inst, 'base_update'); 
                  base.call(this, inst);  
                  if (isDateSelector) {
                      var onAfterUpdate = this._get(inst, 'onAfterUpdate'); 
                    if (onAfterUpdate) onAfterUpdate.apply((inst.input ? inst.input[0] : null), [(inst.input ?                  inst.input.val() : ''), inst]);
              }
            }; 

            $.datepicker._generateHTML = function (inst) {      
              var base = this._get(inst, 'base_generate');     
              var thishtml = base.call(this, inst);     
              var ds = this._get(inst, 'isDateSelector'); 
              if (isDateSelector) {
                thishtml = $('<div />').append(thishtml);                    
                thishtml = thishtml.children();
              }   
              return thishtml;
            };  

            function _hideSDataCalendar() {
                sData.div.hide();
            }

            function _hideEDataCalendar() {         
                eData.div.hide();
            }


            function _handleOnSelect(dateText, inst, type) { 
                var localeDateText = $.datepicker.formatDate(df, new Date(inst.selectedYear, inst.selectedMonth, inst.selectedDay));

                // 0 = sData, 1 = eData
                switch(cnt) {
                case 0:                
                    sData.input.val(localeDateText);
                    eData.input.val('');
                    cnt=1;

                    break;
                case 1: 
                    if (sData.input.val()) {
                        var s = $.datepicker.parseDate(df,sData.input.val()).getTime();
                        var e = $.datepicker.parseDate(df,localeDateText).getTime();
                        if (e >= s) {
                            eData.input.val(localeDateText);  
                            cnt=0;          
                        }
                    }                         
                }               
            }


            function _handleBeforeShowDay(date, type) {
                // Allow future dates?
                var f = (options.allowFuture || date < new Date());

                switch(type)
                {
                  case RangeType.BOTH:             
                    return [true, ((date.getTime() >= Math.min(prv, cur) && date.getTime() <= Math.max(prv, cur)) ?
                    'ui-daterange-selected' : '')];   

                  case RangeType.END:
                    var s2 = null;
                    if (sData.input && sData.input.val()) {
                      try{
                       s2 = $.datepicker.parseDate(df,sData.input.val()).getTime(); 
                      }catch(e){}
                    }

                    var e2 = null;
                    if (eData.input && eData.input.val()) {
                      try {
                       e2 = $.datepicker.parseDate(df,eData.input.val()).getTime();
                      }catch(e){}
                    }

                    var drs = 'ui-daterange-selected';
                    var t = date.getTime();            
                    if (s2 && !e2) {
                      return [(t >= s2 || cnt === 0) && f, (t===s2) ? drs:'']; 
                    }

                    if (s2 && e2) {
                      return [f, (t >= s2 && t <= e2) ? drs:'']; 
                    }

                    if (e2 && !s2) {
                      return [t < e2 && f,(t < e2) ? drs:'']; 
                    }

                    return [f,''];               
                }   
            }

            function _attachCloseOnClickOutsideHandlers() {     
                $('html').click(function(e) {       
                    var t = $(e.target);
                    if (sData.div.css('display') !== 'none') {
                        if (sData.input.is(t) || sData.div.has(t).length || /(ui-icon|ui-corner-all)/.test(e.target.className)) {
                            e.stopPropagation();
                        }else{
                            _hideSDataCalendar();               
                        }   
                    }
                    if (eData && eData.div.css('display') !== 'none') {
                        if (eData.input.is(t) || eData.div.has(t).length || /(ui-icon|ui-corner-all)/.test(e.target.className)) {
                            e.stopPropagation();
                        }else{                  
                            _hideEDataCalendar();
                        }               
                    }
                }); 
            }

            function _alignContainer(data, alignment) {      
                var dir = {right:'left',left:'right'}; 
                var css = {
                  position: 'absolute',
                  top: data.input.position().top + data.input.outerHeight(true)
                };              
                css[alignment ? dir[alignment]:'right'] = '0em';
                data.div.css(css);
            }

            function _handleChangeMonthYear(year, month, inst) {
                // What do we want to do here to sync?
            }

            function _focusStartDate(e) {
                cnt = 0;
                sData.div.datepicker('refresh');        
                _alignContainer(sData,options.opensTo);       
                sData.div.show();     
                _hideEDataCalendar();
            }

            function _focusEndDate(e) {
                cnt = 1;
                _alignContainer(eData,options.opensTo);             
                eData.div.datepicker('refresh');
                eData.div.show();

                sData.div.datepicker('refresh');
                sData.div.hide();
            }

            // Build the start input element  
            sData.input.attr(RangeType.ID, options.endField ? RangeType.START : RangeType.BOTH);
            sData.div.attr('id',sData.input.attr('id')+'_cDiv');
            sData.div.addClass('ui-daterange-calendar');
            sData.div.hide();

            var pDiv = $(document.createElement("DIV"));        
            pDiv.addClass('ui-daterange-container');

            // Move the dom around         
            sData.input.before(pDiv);
            pDiv.append(sData.input.detach());
            pDiv.append(sData.div);

            sData.input.on('focus', _focusStartDate);   
            sData.input.keydown(function(e){if(e.keyCode==9){return false;}});
            sData.input.keyup(function(e){
            _handleKeyUp(e, options.endField ? RangeType.START : RangeType.BOTH);
           });

           _attachCloseOnClickOutsideHandlers(); 

           var sDataOptions = {   
                showButtonPanel: true,
                changeMonth: true,
                changeYear: true,
                isDateSelector: true,    
                beforeShow:function(){sData.input.datepicker('refresh');},
                beforeShowDay: function(date){
                    return _handleBeforeShowDay(date, options.endField ? RangeType.END : RangeType.BOTH);
                },
                onChangeMonthYear: _handleChangeMonthYear,
                onSelect: function(dateText, inst) {
                return _handleOnSelect(dateText,inst,options.endField ? RangeType.END : RangeType.BOTH);
                },
                onAfterUpdate: function(){
                    $('<button type="button" class="ui-datepicker-close ui-state-default ui-priority-primary ui-corner-all" data-handler="hide" data-event="click">Done</button>')    
                        .appendTo($('#'+sData.div.attr('id') + ' .ui-datepicker-buttonpane'))
                        .on('click', function () {
                            sData.div.hide();                   
                    });
                } 
            }; 

            sData.div.datepicker($.extend({}, options, sDataOptions));

            // Attach the end input element
            if (options.endField) {    
              eData.input = $(options.endField);     
              if (eData.input.length > 1 || !eData.input.is("input")) {
               throw "Illegal element provided for end range input!"; 
              }
              if (!eData.input.attr('id')) {eData.input.attr('id','dp_'+new Date().getTime());}
              eData.input.attr(RangeType.ID, RangeType.END);      
              eData.div = $(document.createElement("DIV"));
              eData.div.addClass('ui-daterange-calendar');
              eData.div.attr('id',eData.input.attr('id')+'_cDiv');
              eData.div.hide();

              pDiv = $(document.createElement("DIV"));    
              pDiv.addClass('ui-daterange-container');

              // Move the dom around         
              eData.input.before(pDiv);
              pDiv.append(eData.input.detach());
              pDiv.append(eData.div);  

              eData.input.on('focus', _focusEndDate);     
              // Add Keyup handler
              eData.input.keyup(function(e){
                _handleKeyUp(e, RangeType.END);
              });

              var eDataOptions = {
                showButtonPanel: true,
                changeMonth: true,
                changeYear: true,
                isDateSelector: true,    
                beforeShow:function(){sData.input.datepicker('refresh');},
                beforeShowDay: function(date){
                  return _handleBeforeShowDay(date, RangeType.END);
                },   
                onSelect: function(dateText, inst) {
                  return _handleOnSelect(dateText,inst,RangeType.END);
                },  
                onAfterUpdate: function(){
                    $('<button type="button" class="ui-datepicker-close ui-state-default ui-priority-primary ui-corner-all" data-handler="hide" data-event="click">Done</button>')    
                    .appendTo($('#'+eData.div.attr('id') + ' .ui-datepicker-buttonpane'))
                    .on('click', function () {
                        eData.div.hide();
                    });
                } 
              };

              eData.div.datepicker($.extend({}, options, eDataOptions));
            }

          return {
            // Returns an array of dates[start,end]
            getDates: function getDates() {
              var dates = [];
              var sDate = sData.input.val();
              if (sDate) {
                try {
                  dates.push($.datepicker.parseDate(df,sDate));
                }catch(e){}
              }

              var eDate = (eData.input) ? eData.input.val():null;
              if (eDate) {
                  try {
                    dates.push($.datepicker.parseDate(df,eDate));
                  }catch(e){}
              }
              return dates;
            },

            // Returns the end date as a js date
            getStartDate: function getStartDate() {
              try {
                return $.datepicker.parseDate(df,sData.input.val());
              }catch(e){}
            },

            // Returns the start date as a js date
            getEndDate: function getEndDate() {
              try {
                return $.datepicker.parseDate(df,eData.input.val());  
              }catch(e){}
            }
          };
        }


        var cfg = {startField: '#fromDate', endField: '#toDate',opensTo: 'Left', numberOfMonths: 3, defaultDate: -50};
        var dr = new DateRange(cfg);

     </script>

代码中有一条评论说“允许未来日期？”这就是我试着寻找的地方，但我现在几个小时都没有运气。请帮帮我。

这是我的页面中日期范围选择器的样子：

非常感谢你的帮助。

更新：JSFIDDLE http://jsfiddle.net/dacrazycoder/4Fppd/

Answer 1

在cfg中，添加一个键allowFuture的属性，其值为true

http://jsfiddle.net/4Fppd/85/