如何在asp .net和c#中的gridview中启用选定的行

Question

Here is my aspx:

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" 
        DataKeyNames="ID" DataSourceID="SqlDataSource1" 
        OnRowCommand="GridView1_RowCommand" AutoGenerateSelectButton="True" EnablePersistedSelection="True">
        <Columns>
            <asp:BoundField DataField="ID" HeaderText="ID" InsertVisible="False" 
                ReadOnly="True" SortExpression="ID" />
            <asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name" />
            <asp:BoundField DataField="Class" HeaderText="Class" SortExpression="Class" />
            <asp:BoundField DataField="Section" HeaderText="Section" 
                SortExpression="Section" />
            <asp:BoundField DataField="Address" HeaderText="Address" 
                SortExpression="Address" />
            <asp:TemplateField HeaderText="Edit">
               <ItemTemplate>
                 <asp:Button runat="server" ID="btnedit" Text="Edit" CommandName="EditRow"></asp:Button>                    
               </ItemTemplate>
          </asp:TemplateField>
          <asp:TemplateField HeaderText="Delete">
          <ItemTemplate>
                 <asp:Button runat="server" ID="btndelete" Text="Delete" CommandArgument='<%# Container.DataItemIndex %>' CommandName="Deleterow"></asp:Button>                    
               </ItemTemplate>
          </asp:TemplateField>            
        </Columns>
    </asp:GridView>

here is code behind:

protected void btnsub_Click(object sender, EventArgs e)
        {
            SqlConnection con = Connection.DBconnection();
            if (Textid.Text.Trim().Length > 0)
            {

                SqlCommand com = new SqlCommand("StoredProcedure3", con);
                com.CommandType = CommandType.StoredProcedure;
                com.Parameters.AddWithValue("@id", Textid.Text.Trim());
                com.Parameters.AddWithValue("@Name", Textusername.Text.Trim());
                com.Parameters.AddWithValue("@Class", Textclass.Text.Trim());
                com.Parameters.AddWithValue("@Section", Textsection.Text.Trim());
                com.Parameters.AddWithValue("@address", Textaddress.Text.Trim());
                com.ExecuteNonQuery();
                GridViewRow gr = GridView1.SelectedRow;
                gr.Cells[1].Text = Textusername.Text;
                gr.Cells[2].Text = Textclass.Text;
                gr.Cells[3].Text = Textsection.Text;
                gr.Cells[4].Text = Textaddress.Text;

            }
            else
            {
                SqlCommand com = new SqlCommand("StoredProcedure1", con);
                com.CommandType = CommandType.StoredProcedure;
                com.Parameters.AddWithValue("@Name", Textusername.Text.Trim());
                com.Parameters.AddWithValue("@Class", Textclass.Text.Trim());
                com.Parameters.AddWithValue("@Section", Textsection.Text.Trim());
                com.Parameters.AddWithValue("@address", Textaddress.Text.Trim());
                com.ExecuteNonQuery();
                Response.Redirect("studententry.aspx");
            }
        }

The selected row did not select in gridview. May i know how to enable gridview row. I used msdn and other documents and i followed,but nothing helps.

I design i set enable selection, but still i didn't find out issue.

Can anyone help me?

Thanks,

Answer 1

Basically we get SelectedRow of GridView Upon some GridviewRow Action event like OnSelectedIndexChanged , OnSelectedIndexChanging , OnRowEditing or from Template control like Button click. But here in your coding I don't think your btnsub_Click is inside Gridview so If you want to use the SelectedGridViewRow after your GridviewRow Action event then save the index in some temporary variable or pass the variable to method as argument.

protected void GridView1_SelectedIndexChanged(Object sender, EventArgs e)
  {
    int index = Gridview1.SelectedIndex;
    hiddenfield.Value = index.ToString();
  }

OR In OnRowEditing also you can get the index of row

protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
        {
            if (e.CommandName == "EditRow")
            {
                GridViewRow gr = (GridViewRow)((Button)e.CommandSource).NamingContainer;
                int index = gr.RowIndex;
                hidval.Value = index.ToString();
            }
        }

and on button Click you can get the hiddenfield value as index:

protected void btnsub_Click(object sender, EventArgs e)
        {
            SqlConnection con = Connection.DBconnection();
            if (Textid.Text.Trim().Length > 0)
            {
                SqlCommand com = new SqlCommand("StoredProcedure3", con);
                com.CommandType = CommandType.StoredProcedure;
                com.Parameters.AddWithValue("@id", Textid.Text.Trim());
                com.Parameters.AddWithValue("@Name", Textusername.Text.Trim());
                com.Parameters.AddWithValue("@Class", Textclass.Text.Trim());
                com.Parameters.AddWithValue("@Section", Textsection.Text.Trim());
                com.Parameters.AddWithValue("@address", Textaddress.Text.Trim());
                com.ExecuteNonQuery();
                if(!String.IsNullOrEmpty(hiddenfield.Value))
                {
                int index = Convert.ToInt16(hiddenfield.Value);
                GridView1.Rows[index].Cells[1].Text = Textusername.Text;
                GridView1.Rows[index].Cells[2].Text = Textclass.Text;
                GridView1.Rows[index].Cells[3].Text = Textsection.Text;
                GridView1.Rows[index].Cells[4].Text = Textaddress.Text;
                }

            }
            else
            {
                SqlCommand com = new SqlCommand("StoredProcedure1", con);
                com.CommandType = CommandType.StoredProcedure;
                com.Parameters.AddWithValue("@Name", Textusername.Text.Trim());
                com.Parameters.AddWithValue("@Class", Textclass.Text.Trim());
                com.Parameters.AddWithValue("@Section", Textsection.Text.Trim());
                com.Parameters.AddWithValue("@address", Textaddress.Text.Trim());
                com.ExecuteNonQuery();
                Response.Redirect("studententry.aspx");
            }
        }