让单元格的内容被选中如何写

function checkkexieB21(a) {
var val = document.getElementById ("report1_B21").value;
var cellD21 = document.getElementById("report1_D21");
if(val==1){
cellD21.disabled=false;
cellD21.style.backgroundColor="#FFFFFF";
在这里写几句代码 让cellD21这个单元格中的内容被选中 应该怎么写 
}else {
cellD21.disabled=true;
cellD21.style.backgroundColor="#F5F5F5"
}
}

解决方案 »

  1.   

    cellD21.focus();
    cellD21.select();
      

  2.   

    cellD21.focus();
    cellD21.select();
      

  3.   


    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
    <title>无标题文档</title>
    <script>
     function changeTrColor() 
    {
        var TtrArray=document.getElementById("tablelist").getElementsByTagName("tr");
        for(i=0;i<TtrArray.length;i++)
        {
            TtrArray[i].onclick=function stt(){
                if(this.className!="select")
                    this.className="select";
                else
                    this.className="";
            }
            TtrArray[i].onmouseover=function sdd(){
                if(this.className!="select")
                    this.className="overclass";
            }
            TtrArray[i].onmouseout=function sdd(){
                if(this.className=="select")
                    this.className="select";
                else
                    this.className="";
            }
        }
     }
     window.onload = changeTrColor;
    </script>
    <style>
    .overclass{background:#eee;}
    .select{background:#ccc}
    .tabes{background:#eee;}
    </style>
    </head><body>
    <table width="800" border="1" cellpadding="0" cellspacing="0" class="tablestyle3_table" id="tablelist">
      <tr class="table_th">
        <td>a</td>
     <td>b</td>
     <td>c</td>
     <td>d</td>
      </tr>
      <tr class="table_th">
         <td>a</td>
     <td>b</td>
     <td>c</td>
     <td>d</td>
      </tr>
      <tr class="table_th">
         <td>a</td>
     <td>b</td>
     <td>c</td>
     <td>d</td>
      </tr>
      <tr class="table_th">
         <td>a</td>
     <td>b</td>
     <td>c</td>
     <td>d</td>
      </tr>
    <tr class="table_th">
         <td>a</td>
     <td>b</td>
     <td>c</td>
     <td>d</td>
      </tr>
      <tr class="table_th">
         <td>a</td>
     <td>b</td>
     <td>c</td>
     <td>d</td>
      </tr>
      <tr class="table_th">
         <td>a</td>
     <td>b</td>
     <td>c</td>
     <td>d</td>
      </tr>
      <tr class="table_th">
         <td>a</td>
     <td>b</td>
     <td>c</td>
     <td>d</td>
      </tr>
    </table></body>
    </html>
      

  4.   

    如果是单元格完定就改下
    var TtrArray=document.getElementById("tablelist").getElementsByTagName("tr");
    改成
    var TtrArray=document.getElementById("tablelist").getElementsByTagName("td");