SelectedIndex auto select on page load - asp.net

Question

I have an account page where the user can view their account information.. I want them to be able to change their password here. The Way I have managed to implement it it is as follows:
Web service:
[WebMethod]
public string ChangePassword(DataSet ds)
{
string database = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|/dvd_forum.accdb;Persist Security Info=True";
OleDbConnection myConn = new OleDbConnection(database);
OleDbDataAdapter myDataAdapter = new OleDbDataAdapter("Select * from Users", myConn);
OleDbCommandBuilder builder = new OleDbCommandBuilder(myDataAdapter);
builder.QuotePrefix = "[";
builder.QuoteSuffix = "]";
myConn.Open();
myDataAdapter.Update(ds, "Users");
myConn.Close();
return "Password changed!";
}
Front code:
<asp:Label ID="username" runat="server" Text=""></asp:Label><span>'s Account</span><br />
<asp:TextBox ID="ChangePasswordInput" runat="server"></asp:TextBox>
<asp:Button ID="Button1" runat="server" Text="Save"
onclick="ChangePassword_Click" />
<asp:Label ID="Label2" runat="server" Text=""></asp:Label><asp:RequiredFieldValidator id="RequiredFieldValidator3" runat="server" ErrorMessage="Required!" ControlToValidate="ChangePasswordInput"></asp:RequiredFieldValidator>
<asp:GridView ID="GridView1" runat="server">
</asp:GridView>
back code:
public partial class Account : System.Web.UI.Page
{
public static DataSet ds;
protected void Page_Load(object sender, EventArgs e)
{
if (User.Identity.IsAuthenticated)
{
username.Text = User.Identity.Name;
}
localhost.Service1 myws = new localhost.Service1();
ds = myws.GetUserAcc(User.Identity.Name);
GridView1.DataSource = ds;
GridView1.DataBind();
}
protected void ChangePassword_Click(object sender, EventArgs e)
{
//change password
int i = GridView1.SelectedIndex;
ds.Tables["Users"].Rows[i]["password"] = ChangePasswordInput.Text;
GridView1.DataSource = ds;
GridView1.DataBind();
localhost.Service1 myws = new localhost.Service1();
Label2.Text = myws.ChangePassword(ds);
}
}
The problem with this is that I have to select the row in the gridview before changing the password. Is there any way I can have the row automatically selected as there will only ever be one row.. Or how can I code it differently to work without selecting the row first?
Thanks.

Answer 1

Your GridView and button are separate controls on the page, therefore you can't determine which user is selected for password change, without selecting the row in the GridView. IMO its better if you could put the button inside the GridView. Make an editable GridView.
Edit: Based on your comment that you will only have one row in your grid view, I really don't see the reason of using Gridview with datatable. You can have a label showing user name and textbox for new password. (You may wanna reconfirm the password). Then in your webservice, instead of passing datatable, you may pass the new password (its better if its encrypted) and then update the data using SQL Update statement. But if you still want to use the GridView then instead of getting the selectedIndex you can directly pass 0 in the Row index. You may check if the dataTable contains any row.
if(ds.Tables.Count > 0 && ds.Tables["Users"] != null && ds.Tables["Users"].Rows.Count > 0)
{
ds.Tables["Users"].Rows[0]["password"] = ChangePasswordInput.Text;
    GridView1.DataSource = ds;
    GridView1.DataBind();
    localhost.Service1 myws = new localhost.Service1();
    Label2.Text = myws.ChangePassword(ds);
}