unable to update in gridview when require validation occur in textbox - asp.net

Question

I want to modify items in gridview by update command but in same page i have also a textbox with required validation.
i'm unable to update in gridview when require validation occur in textbox Control
And Source Code here...
<div class="row">
<asp:Button ID="Button1" runat="server" CssClass="btn btn-primary" Text="Add" OnClick="Button1_Click"
ValidationGroup="btn" />
<asp:Button ID="Button2" runat="server" CssClass="btn btn-primary" Text="Reset" OnClick="Button2_Click"
CausesValidation="False" />
<asp:Button ID="Button3" runat="server" CssClass="btn btn-primary" Text="Show" CausesValidation="False"
OnClick="Button3_Click" />
</div>
</form> </div> </div>
<asp:GridView ID="GridView1" runat="server" CssClass="table-hover table-responsive table-condensed table-bordered"
AllowPaging="True" AllowSorting="True" AutoGenerateColumns="False" DataKeyNames="id"
DataSourceID="SqlDataSource1" Visible="False">
<Columns>
<asp:CommandField ShowDeleteButton="True" ShowEditButton="True" />
<asp:BoundField DataField="id" HeaderText="id" InsertVisible="False" ReadOnly="True"
SortExpression="id" />
<asp:BoundField DataField="Loc" HeaderText="Location" SortExpression="Loc" />
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:mycon %>"
SelectCommand="SELECT * FROM [location]" DeleteCommand="Delete From Location Where Id=#id"
UpdateCommand="update location set loc=#loc where id=#id">
<DeleteParameters>
<asp:ControlParameter ControlID="TextBox1" Name="id" PropertyName="Text" />
</DeleteParameters>
<UpdateParameters>
<asp:Parameter Name="loc" />
<asp:ControlParameter ControlID="GridView1" Name="id" PropertyName="SelectedValue" />
</UpdateParameters>
</asp:SqlDataSource>
and cs code here
protected void Button1_Click(object sender, EventArgs e)
{
string qry = "insert into location (loc)values(#loc) ";
SqlConnection con = Connection.Getconnection();
con.Open();
SqlCommand cmd = new SqlCommand(qry, con);
cmd.Parameters.AddWithValue("#loc", TextBox1.Text);
int x = cmd.ExecuteNonQuery();
if (x > 0)
{
ClientScript.RegisterStartupScript(Page.GetType(), "validation!", "<script>alert('Successfully Add')</script>");
}
else
{
ClientScript.RegisterStartupScript(Page.GetType(), "validation!", "<script>alert('Error')</script>");
}
}
protected void Button2_Click(object sender, EventArgs e)
{
TextBox1.Text = string.Empty;
}
protected void Button3_Click(object sender, EventArgs e)
{
GridView1.Visible = true;
}

Answer 1

Please try to add try catch for button1_click to catch Exceptions.
Validation group has an effect only when the value of the CausesValidation property is set to true.and validation group need to specify a value
Please Refer this Link