[求助]GridView鼠标选择行问题【未解决】

html页面：
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" OnRowDataBound="GridView1_RowDataBound"
OnSelectedIndexChanged="GridView1_SelectedIndexChanged">
<Columns>
<asp:BoundField DataField="merID" HeaderText="商品ID" />
<asp:BoundField DataField="merName" HeaderText="商品名称" />
<asp:BoundField DataField="providerid" HeaderText="供应商ID" />
<asp:BoundField DataField="categoryID" HeaderText="分类" />
</Columns>
</asp:GridView>

cs文件代码：
public partial class GridViewSample : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)//添加判断会报错
{
BusinessLogical.DataSource dataSource = new BusinessLogical.DataSource();
this.GridView1.DataSource = dataSource.GetMerchandises("");
this.GridView1.DataBind();
}
}

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
PostBackOptions myPostBackOptions = new PostBackOptions(this);
myPostBackOptions.AutoPostBack = false;
myPostBackOptions.RequiresJavaScriptProtocol = true;
myPostBackOptions.PerformValidation = false;

String evt = Page.ClientScript.GetPostBackClientHyperlink(sender as System.Web.UI.WebControls.GridView, "Select$" + e.Row.RowIndex.ToString());

if (e.Row.RowType == DataControlRowType.DataRow)
{
//单击事件
e.Row.Attributes.Add("onclick", evt);

//当鼠标停留时更改背景色
e.Row.Attributes.Add("onmouseover", "c=this.style.backgroundColor;this.style.backgroundColor='#A9A9A9'");

//当鼠标移开时还原背景色
e.Row.Attributes.Add("onmouseout", "this.style.backgroundColor=c");

//设置悬浮鼠标指针形状为"小手"
e.Row.Attributes["style"] = "Cursor:hand";
}
}
protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
{
Response.Write(this.GridView1.SelectedIndex);
}
}

Page_Load中不加IsPostBack判断，正常；否则，网页就报错

群策群力，大家帮帮忙，谢谢了，^_^

不会吧？你是2005嘛？不知道报啥错哈，config文件要配置<pages enableEventValidation="false"/>

e.Row.Attributes.Add("onclick", evt);这句话就是把onclick和GridView1_SelectedIndexChanged关联起来；

如流川兄说的那样添加选择列问题就简单了，可我想要的效果是鼠标点击GridView行的任何地方，都可以触发SelectedIndexChanged事件