Js中如何获取GridView中的值？

说明：Gridview Id="grdPro" ,上面已经数据，第一列为绑定的文本......
在Js中想取到第一列的值。下面报错；
Gridview 中的转化后的源代码如下：
//
<table cellspacing="0" rules="all" border="1" id="grdPro" style="font-size:9pt;width:99%;border-collapse:collapse;">
<tr>
<th scope="col">短信息内容</th><th scope="col">删除</th>
</tr><tr>
<td>Jerry replied, "Each morning I wake up and say to myself, "Jerry, you have two choices today. You can choose to be in a good mood or you can choose to be in a bad mood." I choose to be in a good mood. Each time something bad happens, I can choose to be a victim or I can choose to learn from it. I choose to learn from it. Every time someone comes to me complaining, I can choose to accept their complaining or I can point out the positive side of life. I choose the positive side of life." </td><td al

参考代码如下：
这是在GridView里面没有控件的情况下,有控件另当别论 ；

var gdview=<%=gridview.ClientID%>;//gridview是GridView控件的ID

或者

var gdview=document.getElementById("<%=gridview.ClientID %>");

//1 读取指定行单元格的值如果是0则读出其表头的值
//rowIndex=1就是第一行的值
function getCellValueByRow(rowIndex)
{
for(var i=0;i<gdview.rows(rowIndex).cells.length;i++)
{
alert(gdview.rows(rowIndex).cells(i).innerText);//弹出指定行单元格的值

}
}

//2 读取指定列单元格的值 cellIndex=0则为第一列的值
function getValueByCell(cellIndex)
{
for(var i=0;i<gdview.rows.length;i++)
{
alert(gdview.rows(i).cells(cellIndex).innerText);//指定列单元格的值
}
}

//3 读取所有单元格的值
function getValueAll(cellIndex)
{
for(var i=1;i<gdview.rows.length;i++)//要从1开始,从0则会读出表头的值
{
for(varj=0;j<gdview.rows(i).cells.length;j++)
{