whole_func_string: function(){
          var TIPS = '请选择', CLASS = 'layui-form-select', TITLE = 'layui-select-title'
          ,NONE = 'layui-select-none', initValue = '', thatInput
          ,selects = elemForm.find('select')
          
          //隐藏 select
          ,hide = function(e, clear){
            if(!$(e.target).parent().hasClass(TITLE) || clear){
              $('.'+CLASS).removeClass(CLASS+'ed ' + CLASS+'up');
              thatInput && initValue && thatInput.val(initValue);
            }
            thatInput = null;
          }
          
          //各种事件
          ,events = function(reElem, disabled, isSearch){
            var select = $(this)
            ,title = reElem.find('.' + TITLE)
            ,input = title.find('input')
            ,dl = reElem.find('dl')
            ,dds = dl.children('dd')
            ,index =  this.selectedIndex //当前选中的索引
            ,nearElem; //select 组件当前选中的附近元素，用于辅助快捷键功能
            
            if(disabled) return;
            
            //展开下拉
            var showDown = function(){
              var top = reElem.offset().top + reElem.outerHeight() + 5 - $win.scrollTop()
              ,dlHeight = dl.outerHeight();
              
              index = select[0].selectedIndex; //获取最新的 selectedIndex
              reElem.addClass(CLASS+'ed');
              dds.removeClass(HIDE);
              nearElem = null;
  
              //初始选中样式
              dds.eq(index).addClass(THIS).siblings().removeClass(THIS);
  
              //上下定位识别
              if(top + dlHeight > $win.height() && top >= dlHeight){
                reElem.addClass(CLASS + 'up');
              }
              
              followScroll();
            }
            
            //隐藏下拉
            ,hideDown = function(choose){
              reElem.removeClass(CLASS+'ed ' + CLASS+'up');
              input.blur();
              nearElem = null;
              
              if(choose) return;
              
              notOption(input.val(), function(none){
                var selectedIndex = select[0].selectedIndex;
                
                //未查询到相关值
                if(none){
                  initValue = $(select[0].options[selectedIndex]).html(); //重新获得初始选中值
                  
                  //如果是第一项，且文本值等于 placeholder，则清空初始值
                  if(selectedIndex === 0 && initValue === input.attr('placeholder')){
                    initValue = '';
                  };
  
                  //如果有选中值，则将输入框纠正为该值。否则清空输入框
                  input.val(initValue || '');
                }
              });
            }
            
            //定位下拉滚动条
            ,followScroll = function(){  
              var thisDd = dl.children('dd.'+ THIS);
              
              if(!thisDd[0]) return;
              
              var posTop = thisDd.position().top
              ,dlHeight = dl.height()
              ,ddHeight = thisDd.height();
              
              //若选中元素在滚动条不可见底部
              if(posTop > dlHeight){
                dl.scrollTop(posTop + dl.scrollTop() - dlHeight + ddHeight - 5);
              }
              
              //若选择玄素在滚动条不可见顶部
              if(posTop < 0){
                dl.scrollTop(posTop + dl.scrollTop() - 5);
              }
            };
            
            //点击标题区域
            title.on('click', function(e){
              reElem.hasClass(CLASS+'ed') ? (
                hideDown()
              ) : (
                hide(e, true), 
                showDown()
              );
              dl.find('.'+NONE).remove();
            }); 
            
            //点击箭头获取焦点
            title.find('.layui-edge').on('click', function(){
              input.focus();
            });
            
            //select 中 input 键盘事件
            input.on('keyup', function(e){ //键盘松开
              var keyCode = e.keyCode;
              
              //Tab键展开
              if(keyCode === 9){
                showDown();
              }
            }).on('keydown', function(e){ //键盘按下
              var keyCode = e.keyCode;
  
              //Tab键隐藏
              if(keyCode === 9){
                hideDown();
              }
              
              //标注 dd 的选中状态
              var setThisDd = function(prevNext, thisElem1){
                var nearDd, cacheNearElem
                e.preventDefault();
  
                //得到当前队列元素  
                var thisElem = function(){
                  var thisDd = dl.children('dd.'+ THIS);
                  
                  //如果是搜索状态，且按 Down 键，且当前可视 dd 元素在选中元素之前，
                  //则将当前可视 dd 元素的上一个元素作为虚拟的当前选中元素，以保证递归不中断
                  if(dl.children('dd.'+  HIDE)[0] && prevNext === 'next'){
                    var showDd = dl.children('dd:not(.'+ HIDE +',.'+ DISABLED +')')
                    ,firstIndex = showDd.eq(0).index();
                    if(firstIndex >=0 && firstIndex < thisDd.index() && !showDd.hasClass(THIS)){
                      return showDd.eq(0).prev()[0] ? showDd.eq(0).prev() : dl.children(':last');
                    }
                  }
  
                  if(thisElem1 && thisElem1[0]){
                    return thisElem1;
                  }
                  if(nearElem && nearElem[0]){
                    return nearElem;
                  }
         
                  return thisDd;
                  //return dds.eq(index);
                }();
                
                cacheNearElem = thisElem[prevNext](); //当前元素的附近元素
                nearDd =  thisElem[prevNext]('dd:not(.'+ HIDE +')'); //当前可视元素的 dd 元素
  
                //如果附近的元素不存在，则停止执行，并清空 nearElem
                if(!cacheNearElem[0]) return nearElem = null;
                
                //记录附近的元素，让其成为下一个当前元素
                nearElem = thisElem[prevNext]();
  
                //如果附近不是 dd ，或者附近的 dd 元素是禁用状态，则进入递归查找
                if((!nearDd[0] || nearDd.hasClass(DISABLED)) && nearElem[0]){
                  return setThisDd(prevNext, nearElem);
                }
                
                nearDd.addClass(THIS).siblings().removeClass(THIS); //标注样式
                followScroll(); //定位滚动条
              };
              
              if(keyCode === 38) setThisDd('prev'); //Up 键
              if(keyCode === 40) setThisDd('next'); //Down 键
              
              //Enter 键
              if(keyCode === 13){ 
                e.preventDefault();
                dl.children('dd.'+THIS).trigger('click');
              }
            });
            
            //检测值是否不属于 select 项
            var notOption = function(value, callback, origin){
              var num = 0;
              layui.each(dds, function(){
                var othis = $(this)
                ,text = othis.text()
                ,not = text.indexOf(value) === -1;
                if(value === '' || (origin === 'blur') ? value !== text : not) num++;
                origin === 'keyup' && othis[not ? 'addClass' : 'removeClass'](HIDE);
              });
              var none = num === dds.length;
              return callback(none), none;
            };
            
            //搜索匹配
            var search = function(e){
              var value = this.value, keyCode = e.keyCode;
              
              if(keyCode === 9 || keyCode === 13 
                || keyCode === 37 || keyCode === 38 
                || keyCode === 39 || keyCode === 40
              ){
                return false;
              }
              
              notOption(value, function(none){
                if(none){
                  dl.find('.'+NONE)[0] || dl.append('<p class="'+ NONE +'">无匹配项</p>');
                } else {
                  dl.find('.'+NONE).remove();
                }
              }, 'keyup');
              
              if(value === ''){
                dl.find('.'+NONE).remove();
              }
              
              followScroll(); //定位滚动条
            };
            
            if(isSearch){
              input.on('keyup', search).on('blur', function(e){
                var selectedIndex = select[0].selectedIndex;
                
                thatInput = input; //当前的 select 中的 input 元素
                initValue = $(select[0].options[selectedIndex]).html(); //重新获得初始选中值
                
                //如果是第一项，且文本值等于 placeholder，则清空初始值
                if(selectedIndex === 0 && initValue === input.attr('placeholder')){
                  initValue = '';
                };
                
                setTimeout(function(){
                  notOption(input.val(), function(none){
                    initValue || input.val(''); //none && !initValue
                  }, 'blur');
                }, 200);
              });
            }
  
            //选择
            dds.on('click', function(){
              var othis = $(this), value = othis.attr('lay-value');
              var filter = select.attr('lay-filter'); //获取过滤器
              
              if(othis.hasClass(DISABLED)) return false;
              
              if(othis.hasClass('layui-select-tips')){
                input.val('');
              } else {
                input.val(othis.text());
                othis.addClass(THIS);
              }
  
              othis.siblings().removeClass(THIS);
              select.val(value).removeClass('layui-form-danger')
              layui.event.call(this, MOD_NAME, 'select('+ filter +')', {
                elem: select[0]
                ,value: value
                ,othis: reElem
              });
  
              hideDown(true);
              return false;
            });
            
            reElem.find('dl>dt').on('click', function(e){
              return false;
            });
            
            $(document).off('click', hide).on('click', hide); //点击其它元素关闭 select
          }
          
          selects.each(function(index, select){
            var othis = $(this)
            ,hasRender = othis.next('.'+CLASS)
            ,disabled = this.disabled
            ,value = select.value
            ,selected = $(select.options[select.selectedIndex]) //获取当前选中项
            ,optionsFirst = select.options[0];
            
            if(typeof othis.attr('lay-ignore') === 'string') return othis.show();
            
            var isSearch = typeof othis.attr('lay-search') === 'string'
            ,placeholder = optionsFirst ? (
              optionsFirst.value ? TIPS : (optionsFirst.innerHTML || TIPS)
            ) : TIPS;
  
            //替代元素
            var reElem = $(['<div class="'+ (isSearch ? '' : 'layui-unselect ') + CLASS 
            ,(disabled ? ' layui-select-disabled' : '') +'">'
              ,'<div class="'+ TITLE +'">'
                ,('<input type="text" placeholder="'+ placeholder +'" '
                  +('value="'+ (value ? selected.html() : '') +'"') //默认值
                  +(isSearch ? '' : ' readonly') //是否开启搜索
                  +' class="layui-input'
                  +(isSearch ? '' : ' layui-unselect') 
                + (disabled ? (' ' + DISABLED) : '') +'">') //禁用状态
              ,'<i class="layui-edge"></i></div>'
              ,'<dl class="layui-anim layui-anim-upbit'+ (othis.find('optgroup')[0] ? ' layui-select-group' : '') +'">'
              ,function(options){
                var arr = [];
                layui.each(options, function(index, item){
                  if(index === 0 && !item.value){
                    arr.push('<dd lay-value="" class="layui-select-tips">'+ (item.innerHTML || TIPS) +'</dd>');
                  } else if(item.tagName.toLowerCase() === 'optgroup'){
                    arr.push('<dt>'+ item.label +'</dt>'); 
                  } else {
                    arr.push('<dd lay-value="'+ item.value +'" class="'+ (value === item.value ?  THIS : '') + (item.disabled ? (' '+DISABLED) : '') +'">'+ item.innerHTML +'</dd>');
                  }
                });
                arr.length === 0 && arr.push('<dd lay-value="" class="'+ DISABLED +'">没有选项</dd>');
                return arr.join('');
              }(othis.find('*')) +'</dl>'
            ,'</div>'].join(''));
            
            hasRender[0] && hasRender.remove(); //如果已经渲染，则Rerender
            othis.after(reElem);          
            events.call(this, reElem, disabled, isSearch);
          });
        }
func_code_string: function(){
          var TIPS = '请选择', CLASS = 'layui-form-select', TITLE = 'layui-select-title'
          ,NONE = 'layui-select-none', initValue = '', thatInput
          ,selects = elemForm.find('select')
          
          //隐藏 select
          ,hide = function(e, clear){
            if(!$(e.target).parent().hasClass(TITLE) || clear){
              $('.'+CLASS).removeClass(CLASS+'ed ' + CLASS+'up');
              thatInput && initValue && thatInput.val(initValue);
            }
            thatInput = null;
          }
          
          //各种事件
          ,events = function(reElem, disabled, isSearch){
            var select = $(this)
            ,title = reElem.find('.' + TITLE)
            ,input = title.find('input')
            ,dl = reElem.find('dl')
            ,dds = dl.children('dd')
            ,index =  this.selectedIndex //当前选中的索引
            ,nearElem; //select 组件当前选中的附近元素，用于辅助快捷键功能
            
            if(disabled) return;
            
            //展开下拉
            var showDown = function(){
              var top = reElem.offset().top + reElem.outerHeight() + 5 - $win.scrollTop()
              ,dlHeight = dl.outerHeight();
              
              index = select[0].selectedIndex; //获取最新的 selectedIndex
              reElem.addClass(CLASS+'ed');
              dds.removeClass(HIDE);
              nearElem = null;
  
              //初始选中样式
              dds.eq(index).addClass(THIS).siblings().removeClass(THIS);
  
              //上下定位识别
              if(top + dlHeight > $win.height() && top >= dlHeight){
                reElem.addClass(CLASS + 'up');
              }
              
              followScroll();
            }
            
            //隐藏下拉
            ,hideDown = function(choose){
              reElem.removeClass(CLASS+'ed ' + CLASS+'up');
              input.blur();
              nearElem = null;
              
              if(choose) return;
              
              notOption(input.val(), function(none){
                var selectedIndex = select[0].selectedIndex;
                
                //未查询到相关值
                if(none){
                  initValue = $(select[0].options[selectedIndex]).html(); //重新获得初始选中值
                  
                  //如果是第一项，且文本值等于 placeholder，则清空初始值
                  if(selectedIndex === 0 && initValue === input.attr('placeholder')){
                    initValue = '';
                  };
  
                  //如果有选中值，则将输入框纠正为该值。否则清空输入框
                  input.val(initValue || '');
                }
              });
            }
            
            //定位下拉滚动条
            ,followScroll = function(){  
              var thisDd = dl.children('dd.'+ THIS);
              
              if(!thisDd[0]) return;
              
              var posTop = thisDd.position().top
              ,dlHeight = dl.height()
              ,ddHeight = thisDd.height();
              
              //若选中元素在滚动条不可见底部
              if(posTop > dlHeight){
                dl.scrollTop(posTop + dl.scrollTop() - dlHeight + ddHeight - 5);
              }
              
              //若选择玄素在滚动条不可见顶部
              if(posTop < 0){
                dl.scrollTop(posTop + dl.scrollTop() - 5);
              }
            };
            
            //点击标题区域
            title.on('click', function(e){
              reElem.hasClass(CLASS+'ed') ? (
                hideDown()
              ) : (
                hide(e, true), 
                showDown()
              );
              dl.find('.'+NONE).remove();
            }); 
            
            //点击箭头获取焦点
            title.find('.layui-edge').on('click', function(){
              input.focus();
            });
            
            //select 中 input 键盘事件
            input.on('keyup', function(e){ //键盘松开
              var keyCode = e.keyCode;
              
              //Tab键展开
              if(keyCode === 9){
                showDown();
              }
            }).on('keydown', function(e){ //键盘按下
              var keyCode = e.keyCode;
  
              //Tab键隐藏
              if(keyCode === 9){
                hideDown();
              }
              
              //标注 dd 的选中状态
              var setThisDd = function(prevNext, thisElem1){
                var nearDd, cacheNearElem
                e.preventDefault();
  
                //得到当前队列元素  
                var thisElem = function(){
                  var thisDd = dl.children('dd.'+ THIS);
                  
                  //如果是搜索状态，且按 Down 键，且当前可视 dd 元素在选中元素之前，
                  //则将当前可视 dd 元素的上一个元素作为虚拟的当前选中元素，以保证递归不中断
                  if(dl.children('dd.'+  HIDE)[0] && prevNext === 'next'){
                    var showDd = dl.children('dd:not(.'+ HIDE +',.'+ DISABLED +')')
                    ,firstIndex = showDd.eq(0).index();
                    if(firstIndex >=0 && firstIndex < thisDd.index() && !showDd.hasClass(THIS)){
                      return showDd.eq(0).prev()[0] ? showDd.eq(0).prev() : dl.children(':last');
                    }
                  }
  
                  if(thisElem1 && thisElem1[0]){
                    return thisElem1;
                  }
                  if(nearElem && nearElem[0]){
                    return nearElem;
                  }
         
                  return thisDd;
                  //return dds.eq(index);
                }();
                
                cacheNearElem = thisElem[prevNext](); //当前元素的附近元素
                nearDd =  thisElem[prevNext]('dd:not(.'+ HIDE +')'); //当前可视元素的 dd 元素
  
                //如果附近的元素不存在，则停止执行，并清空 nearElem
                if(!cacheNearElem[0]) return nearElem = null;
                
                //记录附近的元素，让其成为下一个当前元素
                nearElem = thisElem[prevNext]();
  
                //如果附近不是 dd ，或者附近的 dd 元素是禁用状态，则进入递归查找
                if((!nearDd[0] || nearDd.hasClass(DISABLED)) && nearElem[0]){
                  return setThisDd(prevNext, nearElem);
                }
                
                nearDd.addClass(THIS).siblings().removeClass(THIS); //标注样式
                followScroll(); //定位滚动条
              };
              
              if(keyCode === 38) setThisDd('prev'); //Up 键
              if(keyCode === 40) setThisDd('next'); //Down 键
              
              //Enter 键
              if(keyCode === 13){ 
                e.preventDefault();
                dl.children('dd.'+THIS).trigger('click');
              }
            });
            
            //检测值是否不属于 select 项
            var notOption = function(value, callback, origin){
              var num = 0;
              layui.each(dds, function(){
                var othis = $(this)
                ,text = othis.text()
                ,not = text.indexOf(value) === -1;
                if(value === '' || (origin === 'blur') ? value !== text : not) num++;
                origin === 'keyup' && othis[not ? 'addClass' : 'removeClass'](HIDE);
              });
              var none = num === dds.length;
              return callback(none), none;
            };
            
            //搜索匹配
            var search = function(e){
              var value = this.value, keyCode = e.keyCode;
              
              if(keyCode === 9 || keyCode === 13 
                || keyCode === 37 || keyCode === 38 
                || keyCode === 39 || keyCode === 40
              ){
                return false;
              }
              
              notOption(value, function(none){
                if(none){
                  dl.find('.'+NONE)[0] || dl.append('<p class="'+ NONE +'">无匹配项</p>');
                } else {
                  dl.find('.'+NONE).remove();
                }
              }, 'keyup');
              
              if(value === ''){
                dl.find('.'+NONE).remove();
              }
              
              followScroll(); //定位滚动条
            };
            
            if(isSearch){
              input.on('keyup', search).on('blur', function(e){
                var selectedIndex = select[0].selectedIndex;
                
                thatInput = input; //当前的 select 中的 input 元素
                initValue = $(select[0].options[selectedIndex]).html(); //重新获得初始选中值
                
                //如果是第一项，且文本值等于 placeholder，则清空初始值
                if(selectedIndex === 0 && initValue === input.attr('placeholder')){
                  initValue = '';
                };
                
                setTimeout(function(){
                  notOption(input.val(), function(none){
                    initValue || input.val(''); //none && !initValue
                  }, 'blur');
                }, 200);
              });
            }
  
            //选择
            dds.on('click', function(){
              var othis = $(this), value = othis.attr('lay-value');
              var filter = select.attr('lay-filter'); //获取过滤器
              
              if(othis.hasClass(DISABLED)) return false;
              
              if(othis.hasClass('layui-select-tips')){
                input.val('');
              } else {
                input.val(othis.text());
                othis.addClass(THIS);
              }
  
              othis.siblings().removeClass(THIS);
              select.val(value).removeClass('layui-form-danger')
              layui.event.call(this, MOD_NAME, 'select('+ filter +')', {
                elem: select[0]
                ,value: value
                ,othis: reElem
              });
  
              hideDown(true);
              return false;
            });
            
            reElem.find('dl>dt').on('click', function(e){
              return false;
            });
            
            $(document).off('click', hide).on('click', hide); //点击其它元素关闭 select
          }
          
          selects.each(function(index, select){
            var othis = $(this)
            ,hasRender = othis.next('.'+CLASS)
            ,disabled = this.disabled
            ,value = select.value
            ,selected = $(select.options[select.selectedIndex]) //获取当前选中项
            ,optionsFirst = select.options[0];
            
            if(typeof othis.attr('lay-ignore') === 'string') return othis.show();
            
            var isSearch = typeof othis.attr('lay-search') === 'string'
            ,placeholder = optionsFirst ? (
              optionsFirst.value ? TIPS : (optionsFirst.innerHTML || TIPS)
            ) : TIPS;
  
            //替代元素
            var reElem = $(['<div class="'+ (isSearch ? '' : 'layui-unselect ') + CLASS 
            ,(disabled ? ' layui-select-disabled' : '') +'">'
              ,'<div class="'+ TITLE +'">'
                ,('<input type="text" placeholder="'+ placeholder +'" '
                  +('value="'+ (value ? selected.html() : '') +'"') //默认值
                  +(isSearch ? '' : ' readonly') //是否开启搜索
                  +' class="layui-input'
                  +(isSearch ? '' : ' layui-unselect') 
                + (disabled ? (' ' + DISABLED) : '') +'">') //禁用状态
              ,'<i class="layui-edge"></i></div>'
              ,'<dl class="layui-anim layui-anim-upbit'+ (othis.find('optgroup')[0] ? ' layui-select-group' : '') +'">'
              ,function(options){
                var arr = [];
                layui.each(options, function(index, item){
                  if(index === 0 && !item.value){
                    arr.push('<dd lay-value="" class="layui-select-tips">'+ (item.innerHTML || TIPS) +'</dd>');
                  } else if(item.tagName.toLowerCase() === 'optgroup'){
                    arr.push('<dt>'+ item.label +'</dt>'); 
                  } else {
                    arr.push('<dd lay-value="'+ item.value +'" class="'+ (value === item.value ?  THIS : '') + (item.disabled ? (' '+DISABLED) : '') +'">'+ item.innerHTML +'</dd>');
                  }
                });
                arr.length === 0 && arr.push('<dd lay-value="" class="'+ DISABLED +'">没有选项</dd>');
                return arr.join('');
              }(othis.find('*')) +'</dl>'
            ,'</div>'].join(''));
            
            hasRender[0] && hasRender.remove(); //如果已经渲染，则Rerender
            othis.after(reElem);          
            events.call(this, reElem, disabled, isSearch);
          });
        }
func_documentation_string: 下拉选择框