Select列表操作函数

function moveUp(oSelect,isToTop)
{
     //默认状态不是移动到顶端
     if(isToTop == null) var isToTop = false;
        
     //如果是多选------------------------------------------------------------------
     if(oSelect.multiple)
     {
         for(var selIndex=0; selIndex<oSelect.options.length; selIndex++)
         {
             //如果设置了移动到顶端标志
             if(isToTop)
             {
                 if(oSelect.options[selIndex].selected)
                 {
                     var transferIndex = selIndex;
                     while(transferIndex > 0 && !oSelect.options[transferIndex - 1].selected)
                     {
                         oSelect.options[transferIndex].swapNode(oSelect.options[transferIndex - 1]);
                         transferIndex --;
                     }
                 }
             }
             //没有设置移动到顶端标志
             else
             {
                 if(oSelect.options[selIndex].selected)
                 {
                     if(selIndex > 0)
                     {
                         if(!oSelect.options[selIndex - 1].selected)
                             oSelect.options[selIndex].swapNode(oSelect.options[selIndex - 1]);
                     }
                 }
             }
         }
     }
     //如果是单选--------------------------------------------------------------------
     else
     {
         var selIndex = oSelect.selectedIndex;
         if(selIndex <= 0)
             return;
         //如果设置了移动到顶端标志
         if(isToTop)
         {
             while(selIndex > 0)
             {
                 oSelect.options[selIndex].swapNode(oSelect.options[selIndex - 1]);
                 selIndex --;
             }
         }
         //没有设置移动到顶端标志
         else       
             oSelect.options[selIndex].swapNode(oSelect.options[selIndex - 1]);
     }
}

/**
* 使选中的项目下移
*
* oSelect: 源列表框
* isToBottom: 是否移至选择项到底端，其它依次上移，
*          true为移动到底端，false反之，默认为false
*/
function moveDown(oSelect,isToBottom)
{
     //默认状态不是移动到底端
     if(isToBottom == null)  var isToBottom = false;
        
     var selLength = oSelect.options.length - 1;
    
     //如果是多选------------------------------------------------------------------
     if(oSelect.multiple)
     {
         for(var selIndex=oSelect.options.length - 1; selIndex>= 0; selIndex--)
         {
             //如果设置了移动到底端标志
             if(isToBottom)
             {
                 if(oSelect.options[selIndex].selected)
                 {
                     var transferIndex = selIndex;
                     while(transferIndex < selLength && !oSelect.options[transferIndex + 1].selected)
                     {
                         oSelect.options[transferIndex].swapNode(oSelect.options[transferIndex + 1]);
                         transferIndex ++;
                     }
                 }
             }
             //没有设置移动到底端标志
             else
             {
                 if(oSelect.options[selIndex].selected)
                 {
                     if(selIndex < selLength)
                     {
                         if(!oSelect.options[selIndex + 1].selected)
                             oSelect.options[selIndex].swapNode(oSelect.options[selIndex + 1]);
                     }
                 }
             }
         }
     }
     //如果是单选--------------------------------------------------------------------
     else
     {
         var selIndex = oSelect.selectedIndex;
         if(selIndex >= selLength - 1)
             return;
         //如果设置了移动到底端标志
         if(isToBottom)
         {
             while(selIndex < selLength - 1)
             {
                 oSelect.options[selIndex].swapNode(oSelect.options[selIndex + 1]);
                 selIndex ++;
             }
         }
         //没有设置移动到底端标志
         else       
             oSelect.options[selIndex].swapNode(oSelect.options[selIndex + 1]);
     }
}

/**
* 移动select的部分内容,必须存在value，此函数以value为标准进行移动
*
* oSourceSel: 源列表框对象
* oTargetSel: 目的列表框对象
*/
function moveSelected(oSourceSel,oTargetSel)
{
     //建立存储value和text的缓存数组
     var arrSelValue = new Array();
     var arrSelText = new Array();
     //此数组存贮选中的options，以value来对应
     var arrValueTextRelation = new Array();
     var index = 0;//用来辅助建立缓存数组
    
     //存储源列表框中所有的数据到缓存中，并建立value和选中option的对应关系
     for(var i=0; i<oSourceSel.options.length; i++)
     {
         if(oSourceSel.options[i].selected)
         {
             //存储
             arrSelValue[index] = oSourceSel.options[i].value;
             arrSelText[index] = oSourceSel.options[i].text;
             //建立value和选中option的对应关系
             arrValueTextRelation[arrSelValue[index]] = oSourceSel.options[i];
             index ++;
         }
     }
    
     //增加缓存的数据到目的列表框中，并删除源列表框中的对应项
     for(var i=0; i<arrSelText.length; i++)
     {
         //增加
         var oOption = document.createElement("option");
         oOption.text = arrSelText[i];
         oOption.value = arrSelValue[i];
         oTargetSel.add(oOption);
         //删除源列表框中的对应项
         oSourceSel.removeChild(arrValueTextRelation[arrSelValue[i]]);
     }
}

/**
* 移动select的整块内容
*
* oSourceSel: 源列表框对象
* oTargetSel: 目的列表框对象
*/
function moveAll(oSourceSel,oTargetSel)
{
     //建立存储value和text的缓存数组
     var arrSelValue = new Array();
     var arrSelText = new Array();
    
     //存储所有源列表框数据到缓存数组
     for(var i=0; i<oSourceSel.options.length; i++)
     {
         arrSelValue[i] = oSourceSel.options[i].value;
         arrSelText[i] = oSourceSel.options[i].text;
     }
    
     //将缓存数组的数据增加到目的select中
     for(var i=0; i<arrSelText.length; i++)
     {
         var oOption = document.createElement("option");
         oOption.text = arrSelText[i];
         oOption.value = arrSelValue[i];
         oTargetSel.add(oOption);
     }
    
     //清空源列表框数据，完成移动
     oSourceSel.innerHTML = "";
}

/**
* 删除选定项目
*
* oSelect: 源列表框对象
*/
function deleteSelectItem(oSelect)
{
     for(var i=0; i<oSelect.options.length; i++)
     {
         if(i>=0 && i<=oSelect.options.length-1 && oSelect.options[i].selected)
         {
             oSelect.options[i] = null;
             i --;
         }
     }
}