I have created a User Control(Popupcontrol) and in that control i have created a property(PageType) and when i am using the Popupcontrol on the page then i set the property(pagetype) according to the page.
but now there is some problem i have to two button on the page and on the second button click i want to change the pagetype property .So is there any solution for the same.
Based on your comment, it seems you bind the data (PageType property in your question) in the Page_Load event, instead of this it should be done in overrided DataBind method which should be called if the page is not in post back request (otherwise your data will be overwritting in the next Page_Load event as you mentioned in your comments):
protected void Page_Load(object sender, EventArgs e)
{
if(!Page.IsPostBack)
{
DataBind();
}
}
public override void DataBind()
{
PageType = someValue;
}
after this your click handler may looks like:
protected void button2_Clicked(object sender, EventArgs e)
{
PageType = someOtherValue;
}
Are you setting the variable in a page load event? You may need to add:
if (!Page.IsPostback) {
// Code here.
}
Related
I have a DropDownList and a CheckBox on my web form. After the DropDownList is clicked and this event is posted back to the server. DropDownList_SelectedIndexChanged event is called on the server side. Inside that event handler, I have CheckBox.Checked = true, But I couldn't make the page on the client side to reflect this change (CheckBox.Checked = true). How do I achieve this? Or am I in the wrong direction to use the DropDownList's event handler to update the CheckBox because the page firstly reloads and then DropDownList_SelectedIndexChanged is called?
Page load method:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
this.DropDownList1.Items.Clear();
AddItemsToDropDownList();
}
}
DropDownList selected index changed event handler:
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
var selected = this.DropDownList1.SelectedItem.Text;
CheckBox checkBox = GetCheckBoxToBeSetByText(selected);
checkBox.Checked = true;
}
OK. Found the issue. Actually there is nothing wrong with the code in my original post. But to make a smallest sample when I posted, I removed some "extra" code. The below is the "complete" code (OK, fine, I still removed some code). As you can see, I put the CheckBox into a static Dictionary. Each time the SelectedIndexChanged event handler is called, it's modifying the CheckBox in that static Dictionary, which means it's modifying the CheckBox object created from the last session? (still not clear here) Looks like each time when a postback message is received, a new set of CheckBox objects are created. Bear with me if this is known to everybody here already because I only have two days of experience on this web development thing up to today.
private static Dictionary<Environment, CheckBox> EnvironmentsCheckBoxes;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
EnvironmentsCheckBoxes = new Dictionary<Environment,CheckBox>();
EnvironmentsCheckBoxes.Add(Environment.Dev1, this.Dev1_CheckBox);
EnvironmentsCheckBoxes.Add(Environment.Dev2, this.Dev2_CheckBox);
EnvironmentsCheckBoxes.Add(Environment.QA, this.QA_CheckBox);
EnvironmentsCheckBoxes.Add(Environment.QA2, this.QA2_CheckBox);
EnvironmentsCheckBoxes.Add(Environment.Demo, this.Demo_CheckBox);
EnvironmentsCheckBoxes.Add(Environment.Prod, this.Prod_CheckBox);
EnvironmentsCheckBoxes.Add(Environment.UAT, this.UAT_CheckBox);
}
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
var selected = this.DropDownList1.SelectedItem.Text;
if (selected == "Dev1")
{
EnvironmentsCheckBoxes[Environment.Dev1].Checked = true;
}
else if (selected == "Dev2")
{
...
}
...
}
In .NET i have a gridview which has to display on the mainpage with default settings. So i put it in pageload code. In the same page i have a "List" button; people choose date etc. and when they press the button gridview loads data from another stored procedure. I put that code under List button event. But after people press List button and gridview comes with the needed data, if they press something else (because of page refresh itself) gridview turns back to default settings.
How do i keep the gridview with wanted data?
protected void Page_Load(object sender, EventArgs e)
{
opsbelgegridview.DataSource = DB.OpsHavuzGetir();
opsbelgegridview.DataBind();
protected void listelebtn_Click(object sender, EventArgs e)
{
opsbelgegridview.DataSource = DB.OpsHavuzDetayListeleBtn(tarih1.ToString("yyyy-MM-dd"), tarih2.ToString("yyyy-MM-dd"), durumdd.SelectedItem.Text.ToString(), islemtipdd.SelectedItem.Text.ToString());
opsbelgegridview.DataBind();
You can use IsPostBack() and only load the initial grid on the first load of the page. Then if the grid data changes it will stay.
private void Page_Load()
{
if (!IsPostBack)
{
opsbelgegridview.DataSource = DB.OpsHavuzGetir();
opsbelgegridview.DataBind();
}
}
I created a textbox and a submit button in header(User Control) included in a master page
and I want to use that textbox value after clicking submit in my .aspx.vb page.
How can i access that, as the vb page is loaded first and then master page is loading ?
TextBox Val = (TextBox)this.Master.FindControl("TextBoxID");
The best way to communicate from UserControl to Page/MasterPage is using events
The best way to communicate from MasterPage to Page is using events
On this way you don't hardlink UserControls with their Pages/MasterPages and the Page with it's Master.
Add an event to your UserControl that is raised when the user clicks the button, for example:
In UserControl of type MyControl:
public delegate void SubmittedHandler(MyControl ctrl);
public event SubmittedHandler Submitted;
protected void BtnCLick(object sender, EventArgs e) {
Submitted(this);
}
Then add an handler to this event in your MasterPage, handle it and raise the Master's event again:
In Master's codebehind:
public delegate void MyControlSubmittedHandler(MyControl ctrl);
public event MyControlSubmittedHandler ControlSubmitted;
protected void Page_Init(Object sender, EventArgs e) {
this.MyControl1.Submitted += MyControlSubmitted;
}
protected void MyControlSubmitted(MyControl sender) {
ControlSubmitted(sender);
}
Then add an handler to this event to your page:
In your Page:
protected void Page_Init(object sender, EventArgs e) {
((SiteMaster)Master).ControlSubmitted += MasterControlSubmitted;
}
protected void MasterControlSubmitted(MyControl sender){
// do whatever you need to do
}
If you only need to access the TextBox from the page and you don't need to handle the click-event, you could also use properties to achieve this:
add a public property f.e. MyControlText in your UserControl that get/set the TextBox.Text property
add a public property f.e. MyControlText in your Master that get/set your UserControl's MyControlText property
Now you can get/set this property from your page in this way:
((SiteMaster)Master).MyControlText = "Hello World";
Let's say I have a page with my custom UserControl (containing only asp:Literal and some string property) and a button. Now I want to change Literal's text on button click, so I change my control's string property in button clicked event. Like this:
//in aspx
protected void Button1_Click(object sender, EventArgs e)
{
testControl.Text = "triggered";
}
The problem is my Literal remains unchanged because Page_Load event fires first and creates my custom control, then Button_Clicked fires and changes property but as control is already created, it does nothing. This is my control's code behind:
public partial class TestControl : System.Web.UI.UserControl
{
public string Text { get; set; } }
protected void Page_Load(object sender, EventArgs e)
{
lblTest.Text = Text;
}
}
I figured out that if I move any logic in custom control from Page_Load to property setter it will change like intended. Like this:
public string Text { get { return lblTest.Text; } set { lblTest.Text = value; } }
Is there any other (better) way to do this? My real problem involves much more complicated controls than described here, but problems remains the same: on any postback all properties set in event handlers are ignored.
Moving all logic from Page_Load to Page_PreRender solved the problem. Now properties are set before logic executes. I'll wait for other answers to check if there is better solution and if there are any drawbacks of using Page_PreRender.
This video might help: How Do I: Persist the State of a User Control During a Postback
I have a blank user control (child) and during Page_Load i create some text boxes and a button. I also add an event to the button.
I then load that user control dynamically from a placeholder in another usercontrol (parent).
Both controls are rendered correctly but when i click on the button, the event isnt fired.
Any ideas on how to handle the event?
Child code:
protected void Page_Load(object sender, EventArgs e)
{
/*... other user controls ..*/
UpdateButton = new LinkButton();
UpdateButton.ID = "buttonid";
UpdateButton.Text = "text";
UpdateButton.Click += new EventHandler(UpdateButton_Click);
this.Controls.Add(UpdateButton);
}
protected override void Render(HtmlTextWriter writer)
{
for (int i = 0; i < this.Controls.Count; i++)
{
this.Controls[i].RenderControl(writer);
}
}
public void UpdateButton_Click(object sender, EventArgs e)
{
//Do stuff
}
Parent code:
protected void Page_Load(object sender, EventArgs e)
{
placeholder.Controls.Clear();
ChildControl uc = (ChildControl)LoadControl("~/UserControls/ChildControl.ascx");
placeholder.Controls.Add(uc);
}
If i use the child control directy (ie without the parent the control) the click event is raised and handled nicely. But when i use the parent control, the debugger wont even hit a breakpoint inside UpdateButton_Click().
Thanks in advance.
I think I know what might be happening. In your parent Page_Load you are calling placeholder.Controls.Clear(); This does what you would imagine and clears the control, including any events that have occurred. What happens when remove this line? Do you get an additional one created on each postback?