The DropDownList Control can not refresh problem!!

[JimWu]

Hi all,
If this quest is not belong to this forum, I am sorry.
But I think this question seem to be this forum.
My problem is while I select a dropdownlist's item and click a button but the result do not show my select dropdownlist item.

My code as follows using C#.

 protected void Page_Load(object sender, EventArgs e)
    {
        DropDownList1.AutoPostBack = true;
        DropDownList1.Items.Clear();
        DropDownList1.Items.Add(new ListItem("test1","0"));
        DropDownList1.Items.Add(new ListItem("test2", "1"));
    }
protected void Button1_Click(object sender, EventArgs e)
{
        TextBox1.Text = DropDownList1.SelectedItem.Text;
 }
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
        //DropDownList1.Items.FindByValue();
        DropDownList1.ClearSelection();
        DropDownList1.Items.FindByValue(DropDownList1.SelectedValue).Selected = true;
        TextBox1.Text = DropDownList1.SelectedValue;
}
 

Is something wrong about above code, Have anyone tell me what would I do or do any one have go idea for this problem.
Thanks very much.
Jim

[shweta123]

Hi,

In the page_load , check the page.postBack before filling the dropdownlist .

e.g.

If(page.IsPostBack = False)
{
DropDownList1.Items.Clear();
DropDownList1.Items.Add(new ListItem("test1","0"));
DropDownList1.Items.Add(new ListItem("test2", "1"));

}

Hope this will help.

Hi all,
If this quest is not belong to this forum, I am sorry.
But I think this question seem to be this forum.
My problem is while I select a dropdownlist's item and click a button but the result do not show my select dropdownlist item.

My code as follows using C#.

 protected void Page_Load(object sender, EventArgs e)
    {
        DropDownList1.AutoPostBack = true;
        DropDownList1.Items.Clear();
        DropDownList1.Items.Add(new ListItem("test1","0"));
        DropDownList1.Items.Add(new ListItem("test2", "1"));
    }
protected void Button1_Click(object sender, EventArgs e)
{
        TextBox1.Text = DropDownList1.SelectedItem.Text;
 }
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
        //DropDownList1.Items.FindByValue();
        DropDownList1.ClearSelection();
        DropDownList1.Items.FindByValue(DropDownList1.SelectedValue).Selected = true;
        TextBox1.Text = DropDownList1.SelectedValue;
}
 

Is something wrong about above code, Have anyone tell me what would I do or do any one have go idea for this problem.
Thanks very much.
Jim

[JimWu]

Thanks for your kindly answer.

I am already solve my problem and your suggestion is very assistance for me.

Best regards,
Jim

Hi,

In the page_load , check the page.postBack before filling the dropdownlist .

e.g.

If(page.IsPostBack = False)
{
DropDownList1.Items.Clear();
DropDownList1.Items.Add(new ListItem("test1","0"));
DropDownList1.Items.Add(new ListItem("test2", "1"));

}

Hope this will help.