Dropdownlist change value automatically in AutoPostBack

Hello Programmers

I using dropdownlist with autopostback, its working good but if I select a certain value change this value to another value, I have not any update control like panel.

what is a problem?

"server" Font-Size="Medium" Font-Names="Calibri" CssClass="form-control" Width="250px" Height="30" ID="ddl_device" OnSelectedIndexChanged="ddl_device_SelectedIndexChanged" AutoPostBack="True" >
"">Select Items
"0">CPU
"1">Monitor Extra
"1">laptop
"1">Printer
"1">Fax Machine
"1">Scanner

protected void ddl_device_SelectedIndexChanged(object sender, EventArgs e)
{
if (ddl_device.SelectedValue == "")
{
Response.Write("");
}
else if (ddl_device.SelectedValue == "1")
{
TextBox1.Enabled = true;
TextBox1.Text = "";
TextBox2.Enabled = false;
TextBox2.Text = "";
TextBox3.Enabled = false;
TextBox3.Text = "";
}
else if (ddl_device.SelectedValue == "0")
{
TextBox1.Enabled = true;
TextBox1.Text = "";
TextBox2.Enabled = true;
TextBox2.Text = "";
TextBox3.Enabled = true;
TextBox3.Text = "";
}

2 Replies

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Abdalla Elawad7y ago
Thanks so much Mr.
Priyanka Jain
i fixed this problem when i change just values of items

Select Items
CPU
Monitor Extra
laptop
Printer
Fax Machine
Scanner

THANKS
Priyanka Jain7y ago
Set is not post back on your page load event that may resolve your issue Set if(!IsPostback) Like in the link below https://www.google.com/amp/s/taditdash.wordpress.com/2014/05/21/why-dropdownlist-selectedvalue-not-working-inside-selectedindexchanged-event/amp/