自定义GridView列宽

//显示gridview的表头的宽度。   
int   headWidth   =   10;  
GridView1.Columns[0].HeaderStyle.Width   =   headWidth;  
GridView1.Columns[1].HeaderStyle.Width   =   headWidth;   
//显示gridview的每行的宽度。  
GridView1.Columns[0].ItemStyle.Width   =   headWidth;  
GridView1.Columns[1].ItemStyle.Width   =   headWidth; 

或

<asp:TemplateField>
   <HeaderTemplate>编号</HeaderTemplate>
    <ItemTemplate>
        <div style="width:30px;"><%# Eval("No")%>
        </div>
    </ItemTemplate>
</asp:TemplateField>