Reputation: 518
I have a textbox and a label in ASP.NET and i want to automatically update the label with a value from database that is fetched using the content entered in textbox. This should be done dynamically when the text is changed in textbox and if a match if found in database, the corresponding value should be displayed in the label field (without page refresh). In this case I will enter employee ID in textbox and employee name should be displayed in label. I am using the following code,
<asp:ScriptManager ID="script_manager" runat="server"></asp:ScriptManager>
<asp:UpdatePanel ID="update_name" runat="server">
<ContentTemplate>
<asp:TextBox ID="text_empID" TextMode="Number" MaxLength="6" AutoPostBack="true" OnTextChanged="text_empID_TextChanged" runat="server"></asp:TextBox>
<asp:Label ID="label_empName" runat="server"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
The code behind is as follows,
protected void text_empID_TextChanged(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["DBConnection"].ConnectionString);
con.Open();
SqlCommand cmd = new SqlCommand("select EmployeeName from EmployeeTable where EmployeeID=@id", con);
cmd.Parameters.AddWithValue("@id", text_empID.Text);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
if (dt.Rows.Count > 0)
{
label_empName.Text = dt.Rows[0]["EmployeeName"].ToString();
}
}
But this is not working. Also after entering a value in textbox and if i click outside the box, the text inside disappears. Is there any other way to do this? or am i doing something wrong here?
Upvotes: 0
Views: 2206
Reputation: 4057
I would suggest that you should add a button
because the text_changed
event only fires when the text-box blurs
(loses focus).
That's a very weird behaviour and most users are not used to it and will not expect it.
<ContentTemplate>
<asp:TextBox ID="text_empID" TextMode="Number" MaxLength="6" runat="server></asp:TextBox>
<asp:button id="btnSearch" runat="server" OnClick="text_empID_TextChanged" />
<asp:Label ID="label_empName" runat="server"></asp:Label>
</ContentTemplate>
In any case, have you added a breakpoint? does the event fire? do you get any data back in the DataTable?
EDIT
After your last comment I am convinced that you are clearing the contents of the label on page load.
please, make sure that you only do that in the following context:
protected void Page_Load(object sender, EventArgs e)
{
if(!Page.IsPostBack)
{
label_empName.Text = "";
}
}
Upvotes: 1