Show validation messages of a group on first load of page - asp.net

I checked SO for a solution but I didn't come to anything useful, they were either unanswered like this orphan link or irrelevant. Now I ask it here:
Is it possible to make validators show their messages on first load of the page?
I have a couple of validators (required, custom, range ...) on my page, and I have grouped them. I want the required validation group show their messages on first load (when !page.IsPostBack) so my customer can see what is mandotary and what is not at the first glance.

Following code should work for your requirement.
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
// for all validators to fire, first time
Page.Validate();
// Or Only validators under a specific group will fire
Page.Validate("ValidationGroupName");
}
}

Just call Validate() on the validator(s) from Page_Load.
if(!IsPostBack)
{
this.UserNameRequired.Validate();
// and all the other mandatory validators
}

Sure... just call the submit method of your form.
Isn't that what you really need? submit the form and get all messages?
$(function() {
// this will submit the form, but as you have validation,
// it will fire up all validations
$("form").submit();
});
It's a simple trick, that I sometimes do.

Related

asp.net - RadioButton "CheckedChanged" event does not work when it is unchecked

I have two RadioButtons on my Web Form and here is the code:
protected void RadioButton1_CheckedChanged(object sender, EventArgs e)
{
}
protected void RadioButton2_CheckedChanged(object sender, EventArgs e)
{
Response.Write(DateTime.Now.ToLongTimeString());
}
When I check RadioButton2, time appears on the page but when I check RadioButton1(RadioButton2 is unchecked now) it does not update the shown time and removes it.
the event function must be called when it checks and unchecks.I don't understand what is wrong here and why the time disappears
(As it is obvious, I know about GroupName property and AutoPostBack. My problem is something else)
You can check property of each control and check AutoPostBack=True
and also if checked="true"
I tried it on different ways and opened my pages with different browsers and I figured out a few things. the most important of them which is related to my problem:
When a control Calls back, the page refreshes and that is why the time disappears. It sends the status of all controls using post method to itself and they would be the same way as they were. But the time is not written on a control and it would not be saved.
As I said if it was for example on a Label, the text would be kept:
Label1.Text = DateTime.Now.ToLongTimeString();
It answers the first question but I still think that the event function must be called when the RadioButton is being unchecked.

asp.net dynamic user control button click issue

I made researching about this subject I could not find proper answer.
In my default.aspx page, I have a treeview. Codes are in default.aspx like below:
protected void Page_Load(object sender, EventArgs e)
{
}
protected void TreeView1_SelectedNodeChanged(object sender, EventArgs e)
{
Control ucont;
if (TreeView1.SelectedNode.Value == "Yeni Dönem")
{
ucont = LoadControl("usercontrols/yenidonem.ascx");
PlaceHolder1.Controls.Add(ucont);
}
else
{
ucont = LoadControl("usercontrols/tabloktar.ascx");
PlaceHolder1.Controls.Add(ucont);
}
}
I load user controls dnynmicaly. User controls are have button control. I can not fire user control's button click when I load it dynamcally. How can I solve this ?
Thanks.
First of all, I would not recommend adding control dynamically later than in Page_Load event. Other things to remember is that You should add it on each page load and assign unique ID value the control that does not change between postbacks.
In this case, the easiest way would be to always add both controls to the page and show appropriate one using Visibility property.
If that's not suitable for You, try to move the code from TreeView1_SelectedNodeChanged to the Page_Load event and load appropriate control on each postback until it should be changed to another one.
I haven't tested this, so if You have any issues when using thise answer, let me know in the comments and I'll try to help.

My code says a checkbox isn't checked when it is... ASP.NET

I have some checkboxes on a page. I get them using FindControl() in an UpdatePanel after pressing a button trigger, but the checked value is wrong. How can I get the correct checked value?
If you have any code that sets the values of the checkboxes on your page, make sure it isn't executing on postbacks, like this:
protected void Page_Load(object sender, EventArgs e) {
// Only set the checkboxes on GETs, not on POSTs
if (! this.IsPostBack) {
this.EmailMeUpdatesCheckbox.Value = false;
}
}
Actions triggered within UpdatePanels still go through the page lifecycle (which is why you have access to all your Page's state), so it may be clearing the user's selections before getting to the code in which you examine the checkbox values.

how can I reload an update panel onclient side using javascript?

I have a gridview button that I programmatically created and I want to load an update panel on the client side with the sent data. I have a hidden value field that gets its data on the click of the gridview button and the dropdownlist in my updatepanel depends on that value.
while calling __doPostBack directly will work, it's not a perfect solution because the name of that function is strictly speaking an implementation detail of the .Net framework.
A better solution is to use ClientScriptManager.GetPostBackEventReference, which gives you a more resilient interface to the same functionality. Do note that GetPostBackEventReference and GetCallBackEventReference are not the same thing - the former causes a page reload (partial or full, depending on how your UpdatePanels are set up), while the latter doesn't.
The easiest way to do this is to call __doPostBack from client side.
On client side button1_onclick method, calls:
__doPostBack('<%=UpdatePanel1.ClientID %>','Refresh:0,1,2'); //refresh update panel
On page behind add the following event handler to capture the post back call:
protected void UpdatePanel1_Load(object sender, EventArgs e)
{
string arg = Request.Form["__EVENTARGUMENT"];
if (string.IsNullOrEmpty(arg)) return;
if (arg.StartWith("Refresh")
{
//parse data first then do your thing here...
}
}
And of course don't forget to wire event to the above method:
protected void Page_Init(object sender, EventArgs e)
{
UpdatePanel1.Load += new EventHandler(UpdatePanel1_Load);
}
we use the __dopostback() method which simulates a postback and causes the updatepanel to refresh
__doPostBack('controlName','');
Don't forget that the control name is it's HTML ID (which may well contain dollars etc) and not just it's ASP.NET ID.
As far as I know you can either call this method and pass in the hidden value field, or the div that it is in.

Prevent hiding of ModalPopupExtender when ok or cancel is clicked

I am using an ASP.NET ModalPopupExtender on a page and would like to prevent the dialog from hiding when the user presses the ok button in certain conditions. But I can't seem to find a way.
What I am looking for is something like this
ajax:ModalPopupExtender
...
OnOkScript="return confirm('You sure?')"
...
if confirm is false, then the modal dialog doesn't disappear.
From my understanding in your specific situation you would not wire up the button, and just wire up a script to handle the conditional, then you can close it via JS.
The following JavaScript function will allow you to achieve this:
function conditionalHide(clientID)
{
if (confirm('You sure?'))
{
$find(clientID).hide();
}
}
You can wire this up to your asp:Button control in the Page_Load event of your page
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
btnOK.OnClientClick = string.Format("conditionalHide('{0}'); return false;",
panPopup_ModalPopupExtender.ClientID);
}
}
Some notes:
panPopup_ModalPopupExtender is your ModalPopupExtender
The return false; prevents a postback from occurring when the user clicks the button
You could hard-code the ClientID of the ModalPopupExtender, but this introduces an (additional) maintainance headache. The approach shown is the best one that I've found to alleviate this overhead

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