I have a drop down box that populates textbox values based on its value. It fires when it is changed but on pageload it doesnt fire. How do I get it to fire on page load?
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
TextBox3.Text = DropDownList1.SelectedValue;
TextBox12.Text = DropDownList1.SelectedValue;
TextBox21.Text = DropDownList1.SelectedValue;
//etc
Tim Schmelter's comment is right on the money.
// Wire up to the page load event
protected void Page_Load(object sender, System.EventArgs e)
{
updateTextBoxes();
}
// Wire up to the select index-changed event
protected void DropDownList1_SelectIndexChanged( object sender, EventArgs e )
{
updateTextBoxes();
}
// your workhorse method
protected void updateTextBoxes()
{
TextBox3.Text = DropDownList1.SelectedValue;
TextBox12.Text = DropDownList1.SelectedValue;
TextBox21.Text = DropDownList1.SelectedValue;
// etc.
}
It won't be called automatically at page load, you have to call it "manually":
void Page_Load(object sender, System.EventArgs e) {
// ....
DropDownList1_SelectedIndexChanged(DropDownList1, e);
}
SelectedIndexChanged fires in response to a user-driven change. Move the assignment logic to another method and call it manually from Page_Load and also from your event handler.
Related
Is there a way that I force all TextBoxes (as an example) .. on an asp.net form, to go through the same routine, during a "postback" event or onchange event?
Here is example code.
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
textBox1.TextChanged += new EventHandler(textBox_TextChanged);
textBox2.TextChanged += new EventHandler(textBox_TextChanged);
}
}
protected void textBox_TextChanged(object sender, EventArgs e)
{
}
The Drop Down Lists in the FooterTemplate gets unpopulate when clicking "update" on some row
this is the page load event when they gets populate:
protected void Page_Load(object sender, EventArgs e)
{
DropDownList ddlImages_new = ((DropDownList)gvAdminArticleAdd.FooterRow.FindControl("ddlImages_new"));
ddlImages_new.DataSource = GetPdfs();
ddlImages_new.DataBind();
DropDownList ddl_invNamesNew = ((DropDownList)gvAdminArticleAdd.FooterRow.FindControl("ddl_invNamesNew"));
ddl_invNamesNew.DataSource = GetInvestigatorNames();
ddl_invNamesNew.DataBind();
}
If I click the update linkButton on some row the data in the drop down lists are disappear
Even when try to call the page load on cancel event it didn't work.
protected void gvAdminArticleAdd_CancelEditEventHandler(object sender, GridViewCancelEditEventArgs e)
{
Page_Load(sender, e);
}
Bind your controls only when the page is not post back:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
DropDownList ddlImages_new = ((DropDownList)gvAdminArticleAdd.FooterRow.FindControl("ddlImages_new"));
ddlImages_new.DataSource = GetPdfs();
ddlImages_new.DataBind();
DropDownList ddl_invNamesNew = ((DropDownList)gvAdminArticleAdd.FooterRow.FindControl("ddl_invNamesNew"));
ddl_invNamesNew.DataSource = GetInvestigatorNames();
ddl_invNamesNew.DataBind();
}
}
I'm trying to set an initial selection for a DropDownList by calling: drop.SelectedIndex = 5 in Page_Load.
This works, but then if I change the selection manually and want to save the form, I'm still getting the initial selection instead of the new selection when calling drop.SelectedValue. What's wrong?
You have forgotten you check if(!IsPostback). Otherwise you will select the 6th item again on postbacks before the SelectedIndexChanged event is triggered (or a button-click event):
protected void Page_Load(Object sender, EventArgs e)
{
if(!IsPostBack) // do this only on the initial load and not on postbacks
dropDwonList1.SelectedIndex = 5;
}
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
//set up data here
}
}
if (Page.IsPostBack)
{
//do page reload logic in here
}
protected void foo(object sender, EventArgs e)
{
//get your selected value here
}
Try this code
You should be using if(!IsPostback) in the Page_Load function.
protected void Page_Load(Object sender, EventArgs e)
{
if(!IsPostBack)
{
drop.SelectedIndex = 5;
//yourcode
}
}
Through this your problem will be solved
I am creating a button dynamically and place it in a placeholder as below
<asp:Button ID="generateTableSchema" runat="server" Text="Generate Table" OnClick="generate_Click" />
protected void generate_Click(object sender, EventArgs e)
{
Button button = new Button();
button.Text = "Generate Table";
button.ID = "generateTable";
button.OnClick = hello();
PlaceHolder1.Controls.Add(button);
}
but onclick event is not firing.
this is the error i am getting
System.Web.UI.WebControls.Button.OnClick(System.EventArgs)' is inaccessible due to its protection level
hello is as below...
public void hello()
{
Label1.Text = "heellllllllllo";
}
What's wrong here????
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
}
else
{
button.Click += ButtonClick;
}
}
#Daren u mean like this...
Because you are adding the button programmatic ally you have to add the event handler.
So this would work..
EDIT
Wrapped the button INSIDE Page_Load
protected void Page_Load(object sender, EventArgs e)
{
Button button = new Button();
button.Text = "Generate Table";
button.ID = "generateTable";
button.Click += hello; /// THIS is the handler
PlaceHolder1.Controls.Add(button);
}
ButtonClick would be the name of your method.
protected void hello(Object sender, EventArgs e)
{
// ...
}
Also, as you're generating this at runtime you need to makesure this gets called on postbacks too.
The OnClick is a protected method. You should use the event Click.
button.Click += new EventHandler(Click);
public void hello(object sender, EventArgs e)
{
Label1.Text = "heellllllllllo";
}
By the way, make sure you create and add the control in every postback, otherwise the event won't work.
Change button.OnClick = hello(); to:
button.Click += new EventHandler(hello);
And change the definition for hello() to:
protected void hello(object sender, EventArgs e)
{
Label1.Text = "heeellllllo";
}
The event is called Click. You need to add the event handler with the correct signature:
button.Click += new EventHandler(hello);
and the signature is:
protected void hello(Object sender, EventArgs e)
{
// ...
}
How to: Add an Event Handler Using Code
Note that you need to recreate dynamical controls on every postback.
You assigning the result of executing hello().
Try assigning:
button.OnClick = hello;
-- edit--
apparantly, that does not clarify your error.
Add the handler to the event handler in stead:
button.Click += hello;
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
}
else if(Page.IsPostBack && Label11.Text=="yes")
{
Button button = new Button();
button.Text = "Generate Table";
button.ID = "generateTable";
button.Click += ButtonClick;
PlaceHolder1.Controls.Add(button);
}
}
setting
Label11.Text = "yes";
in generate_click.
protected void ButtonClick(object sender, EventArgs e)
{
Label1.Text = "heeellllllo";
}
Having to use pre render is causing me problems.. It would be great if I did not need it.. The problem is I have the list in a user control and when I goto the next 'page' I databind.. but then the datapager prerenders.. which also does a batabind.. so it runs twice..
If I remove the prerender .. then clicking next 'page' does nothing..
Any idea?
protected void Page_Load(object sender, EventArgs e)
{
GetSearchResults();
}
//protected void dpMembers_PreRender(object sender, EventArgs e)
//{
// GetSearchResults();
//}
public void GetSearchResults()
{
List<Person> listPerson = new List<Person>();
string strServer = "localhost";
string strAppPath = Server.MapPath("/");
PersonBusiness pb = new PersonBusiness(new PersonRepository());
listPerson = pb.GetAllPersons(strServer, strAppPath);
lvPersons.DataSource = listPerson;
lvPersons.DataBind();
}
Modify your Page load to
protected void Page_Load(object sender, EventArgs e)
{
if(!Page.IsPostBack)
{
GetSearchResults();
}
}
your prerender seems ok.