Input string was not in a correct format

Question

I use this below code in .aspx file for delete Girdview row. 

 

Asp Code:

 

<asp:TemplateField HeaderText="mus_id">

<ItemTemplate>

<asp:LinkButton ID="lblDelete" CommandArgument='<%# Eval("mus_id") %>' CommandName="DeleteRow" runat="server">Delete</asp:LinkButton>

</ItemTemplate>

</asp:TemplateField>

 

C# Code

 

protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)

{

if(e.CommandName == "DeleteRow")

{

SqlConnection cs = new SqlConnection("Data Source=DESKTOP-3T94FQ0;Initial Catalog=RAMS;Integrated Security=False;UID=sa;Password=sa123;");

SqlCommand deleteCommand = new SqlCommand("DELETE FROM [tbl_musannet] WHERE [mus_id]= @mus_id",cs);

deleteCommand.Parameters.Add("@mus_id", SqlDbType.BigInt).Value = Convert.ToInt64(e.CommandName);

cs.Open();

deleteCommand.ExecuteNonQuery();

cs.Close();

}

}

 

But when I going to delete rows "Input string was not in a correct format" error is showing. 

Please help.

Thanks