I have textbox control with auto postback = "true" in update panel and there is save button with access key of "Alt + s" when i change something into textbox and without losing focus if user has pressed "Alt + s" than need to call first text change event of textbox and then should fire save click event once as there is some calculation on text change event.In this situation first it fires text change event than it call save click event and than it calls again text change event.
Is there any good approach to resolve issue either client side or server side or from sql side?
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:TextBox ID="Txt_Val" runat="server" AutoPostBack="True"
OnTextChanged="Txt_Val_TextChanged"></asp:TextBox>
<asp:Button ID="Btn_Save" runat="server" OnClick="Btn_Save_Click"
Text="Save" AccessKey="S" ValidationGroup="S"/>
</ContentTemplate>
</asp:UpdatePanel>
protected void Btn_Save_Click(object sender, EventArgs e)
{
//Save data into database
}
protected void Txt_Val_TextChanged(object sender, EventArgs e)
{
// Some calculation
}
Solution 1 :
Here the Microsoft provide the Control.Update Method documentation here https://learn.microsoft.com/en-us/dotnet/api/system.windows.forms.control.update?view=netframework-4.8. its last update value store in Database.
Solution 2 :
please check your event its some another event call then sometimes this issue is given.
Solution 3 :
you Set focus after a update a value in the page load event
protected void Page_Load(object sender, EventArgs e)
{
TextBox1.Focus();
}
second time set focus and after update is a 3rd solution for this issue.
I hope the above three solutions is helpful.
when i change something into textbox and without losing focus if user has pressed "Alt + s" than need to call first text change event of textbox and then should fire save click event once as there is some calculation on text change event
quoted statement can also be handled like this:
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:TextBox ID="Txt_Val" runat="server" AutoPostBack="True"
OnTextChanged="Txt_Val_TextChanged"></asp:TextBox>
<asp:Button ID="Btn_Save" runat="server" OnClick="Btn_Save_Click"
Text="Save" AccessKey="S" ValidationGroup="S" OnClientClick="return verifyFirst();" />
</ContentTemplate>
</asp:UpdatePanel>
<script>
function verifyFirst(){
return verifyChangedText($('[id$=Txt_Val]'));
}
function verifyChangedText(elem){
//verify your stuff on client level.
//if you need to do the server side stuff, hit WebMethod using ajax
//finally according to the result
if(everythingIsOk){
return true;
}
return false;
}
</script>
onClientClick executes first on client side, if everything is satisfactory the return bool value if true it executes the server side event call OnClick="Btn_Save_Click" and if its false then it doesn't execute the server side event call.
UPDATED
I have multiple textboxes with text change event on page or in grid for each text box control it will be difficult to handle
as per your comment quoted above, you can handle multiple TextBox verification
but it can only be handled in following manner:
if a user presses enter without focusing out then we don't know on which TextBox user made changes to so we will have to check all the TextBoxes present in the form and fire each TextBox's onkeypress event.
for e.g:
i = 0;
function verifyMe(event,args){
debugger;
$(args).text(i += 1);
};
function verifyThisStuff(){
var e = jQuery.Event("keypress");
$('.forVerification').each(function(){
$(this).trigger(e);
});
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="text" class="forVerification" onkeypress="return verifyMe(event,'#span1');">
<input type="text" class="forVerification" onkeypress="return verifyMe(event,'#span2');">
<button type="button" onclick="return verifyThisStuff();">click Me</button>
<p>textbox 1 Keypresses: <span id="span1">0</span></p>
<p>textbox 2 Keypresses: <span id="span2">0</span></p>
Related
There appears to be a hundred questions that are very similar, but none seem to solve my issue.
I have a very basic bootstrap webform with two textboxes - each accepts a serial number that is populated by a handheld scanner attached to the PC. When the user scans the first barcode, the TextChanged event for txtLabelA fires a method that validates the serial number and switches focus to txtLabelB. When the user scans the second barcode it fires the TextChanged event for txtLabelB. This inserts the two values into a cross reference table in the database, displays a success message and clears the form for the next set of serial numbers. Very straight forward. This has worked flawlessly for a long time.
However, recently I was asked to add a button to the form that allows the user to manually type in a serial number and click Submit. This has now mucked everything up, because clicking the Submit button fires the OnClick AND the OnTextChanged events causing the form to postback twice. How can I prevent this?
<div class="card-body">
<div class="form-group">
<asp:TextBox ID="txtLabelA" runat="server" EnableViewState="true" CssClass="form-control" AutoPostBack="true" OnTextChanged="txtLabelA_TextChanged"></asp:TextBox>
<span class="help-block"></span>
</div>
<div class="form-group">
<asp:TextBox ID="txtLabelB" runat="server" EnableViewState="true" CssClass="form-control" AutoPostBack="true" OnTextChanged="txtLabelB_TextChanged"></asp:TextBox>
<span class="help-block"></span>
</div>
<div class="form-group">
<asp:Button ID="btnSubmit" runat="server" Text="Submit" CssClass="btn btn-primary" OnClick="btnSubmit_Click" />
<asp:Button ID="btnCancel" runat="server" Text="Clear" CssClass="btn btn-secondary" OnClick="btnCancel_Click" />
<div style="margin-top: 10px;">
<p>
<asp:Label ID="lblError" runat="server" CssClass="text-danger"></asp:Label>
<asp:Label ID="lblSuccess" runat="server" CssClass="text-success"></asp:Label>
</p>
</div>
</div>
</div>
Here is a snippet of the code behind (not much to it):
protected void txtLabelA_TextChanged(object sender, EventArgs e)
{
GetLabelDetails();
}
protected void txtLabelB_TextChanged(object sender, EventArgs e)
{
SyncLabels();
}
protected void btnSubmit_Click(object sender, EventArgs e)
{
SyncLabels();
}
I have even tried changing the button's OnClick event to be the OnTextChanged event, but it didn't help.
Does anyone have any thoughts?
Thanks.
Ok folks, we found a solution. I merged the suggestions of both posters above to find a resolution. I started with Daniel's suggestion to put nothing in the button's click event to ensure it would not trigger the SyncLabels() method, but that alone did not completely solve it because the event itself was still causing a postback. The trick was including Bmils' note above to add a meaningless javascript function to the OnClientCLick() event of the button. This allowed me to "return: false;", effectively blocking the second postback on the client side. Thank you both for your input. I wouldn't have resolved this with your help.
https://learn.microsoft.com/en-us/dotnet/api/system.web.ui.webcontrols.textbox.autopostback?view=netframework-4.8
Use the AutoPostBack property to specify whether an automatic postback to the server will occur when the TextBox control loses focus. Pressing the ENTER or the TAB key while in the TextBox control is the most common way to change focus.
In my personal experience, barcode scanners essentially mimic a user typing in a barcode number and then pressing ENTER. If a user manually types in a barcode number and then clicks on the Submit button, then the TextBox is losing focus anyway and causing the additional Postback.
Recommendation: Remove the Button.Click event (or at least the logic within the Click handler.)
Note: If the TextBox control's parent container contains a button marked as the default button (for example, if the container's DefaultButton or DefaultButton property is set), the default button's Click event is not raised in response to the automatic postback.
In my web application I need a functionality so that when users click on textbox to input values, it should make the button and the other fields visible?
I am using the code provided below but, could not get it working.
C#:
protected void TextBox1_Click(object sender, EventArgs e)
{
ButtonSearch.Visible = true;
}
ASP.NET:
<asp:TextBox ID="TextBox1" runat="server" OnTextChanged="TextBox1_TextChanged" OnClick="TextBox1_Click"></asp:TextBox>
<asp:Button ID="ButtonSearch" runat="server" OnClick="ButtonSearch_Click" Text="Search" Visible="False" />
How to accomplish this?
Set AutoPostback="True". This way the event will be fired server-side, and the button will become visible.
<asp:TextBox ID="TextBox1" runat="server" OnTextChanged="TextBox1_TextChanged" OnClick="TextBox1_Click" AutoPostBack="true"></asp:TextBox>
However, if you only want to toogle visility of a button, you really should considerate javascript. This will save a trip back to the server.
<asp:TextBox onclick="txtBox1_ClientClicked()" ID="TextBox1" runat="server" OnClick="TextBox1_Click"></asp:TextBox>
<asp:Button ID="ButtonSearch" runat="server" OnClick="ButtonSearch_Click" Text="Search" style="display:none;" />
<script type="text/javascript">
function txtBox1_ClientClicked(){
var theButton = document.getElementById('<%=ButtonSearch.ClientID%>');
theButton.style.display = 'block';
}
</script>
You do not need to post back to the server to accomplish your job. You can use client side onFocus event and javascript/jquery, for example.
I know I used an input of type text, and you are using an ASP Control which posts on server, but here is a JSFiddle to get you on the right track: http://jsfiddle.net/Mmjtz/1/
$("<%= ButtonSearch.ClientID %>").click(function(){
$("#TextBox1").show():
});
In this code you need to pass fields ID which you want to visible on the click of button.
Put the textbox inside a div and use the div's onClick event from codebehind. It's not what you asked but it works for me without any errors. Here is a javascript function to implement requested event:
function toggleVisibility()
{
document.getElementById('TextBox1').disabled = true;
/*
...some other code...
*/
}
And of course, you have to define your onclick event at the div definition after implementing this JS function.
<div id="TBdiv" onClick="toggleVisibility()">
<asp:TextBox ID="TextBox1"..../>
</div>
IMPORTANT: Since you now disabled your TextBox from codebehind, you have to enable it in somewhere before you want to use it again. Otherwise you will not see it while the page is running.
jQuery is the perfect solution for your problem. The code would be something like this:
$("#TextBox1").on("click",function(){$("#ButtonSearch").css("visibility", "visible");})
You include the script by adding <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script> to the page and then you can add the piece of code above to within <script></script> tags.
How can I check whether a particular button was clicked or not in ASP.NET?
I think I need to perform some operation on Page_Load. This shouldn't be entering to Button_Click event to find. Is there any way that I can find where it was clicked or not on Client Side and take it to Page_Load?
Background: Basically __EVENTTARGET and __EVENTARGUMENT , These two Hidden controls are added to the HTML source, when ever any autopostback attribute is set to true for any of the web control.
The __EVENTTARGET hidden variable will tell the server ,which control actually does the server side event firing so that the framework can fire the server side event for that control.
The __ EVENTARGUMENT variable is used to provide additional event information if needed by the application, which can be accessed in the server.
So we can easily get the control causing postback using:Request.Params.Get("__EVENTTARGET");
PROBLEM:
The method: Request.Params.Get("__EVENTTARGET"); will work for CheckBoxes, DropDownLists, LinkButtons, etc.. but this does not work for Button controls such as Buttons and ImageButtons
The Button controls and ImageButton controls does not call the __doPostBack function. Because of this, the _EVENTTARGET will always be empty. However, other controls uses javascript function __doPostBack to trigger postback.
So, I will suggest to do something as below. Add an OnClientClick property to the buttons. Also, define a hiddenField in your Markup, whose value will contain the actual button causing postback.
<asp:Button ID="Button1" runat="server" Text="Button"
OnClientClick = "SetSource(this.id)" />
<asp:ImageButton ID="ImageButton1" runat="server"
OnClientClick = "SetSource(this.id)" />
<asp:HiddenField ID="hidSourceID" runat="server" />
On the OnClientClick property of the Button and ImageButton Call the SetSource JavaScript function
<script type = "text/javascript">
function SetSource(SourceID)
{
var hidSourceID =
document.getElementById("<%=hidSourceID.ClientID%>");
hidSourceID.value = SourceID;
}
</script>
Here onwards, you can very easily check in your Page_Load as to which Control caused postback:
if (IsPostBack)
{
string CtrlName;
CtrlName=hidSourceID.Value;
}
I just got the same trouble, have to do some logic judgement in the Page_Load method to treat different event(which button was clicked).
I realize the arm to get the as the following example.
The front end aspx source code(I have many Buttons with IDs F2, F3, F6, F12.
<Button Style="display: none" ID="F2" runat="server" Text="F2:Cancel" OnClientClick="SeiGyo(this)" OnClick="F2_Click" />
<Button Style="display: none" ID="F3" runat="server" Text="F3:Return" OnClientClick="SeiGyo(this)" OnClick="F3_Click" />
<Button Style="display: none" ID="F6" runat="server" Text="F6:Run" OnClientClick="SeiGyo(this)" OnClick="F6_Click" />
<Button Style="display: none" ID="F12" runat="server" Text="F12:Finish" OnClientClick="SeiGyo(this)" OnClick="F12_Click" />
The back end aspx.cs source code, what I need to do is judge which button was clicked when Page_Load was triggered. It seems a little stupid, but works.
In your situation, the button be clicked will be added into dic. I hope that will be helpful to some one.
Dictionary<string, string> dic = new Dictionary<string, string>();
foreach(var id in new string[]{"F2","F3","F6","F12"})
{
foreach (var key in Request.Params.AllKeys)
{
if (key != null && key.ToString().Contains(id))
dic.Add(id, Request[key.ToString()].ToString());
}
}
The UniqueID of the button will be in Request.Form["__EVENTTARGET"]
This question is already answered at: ASP.NET : Check for click event in page_load
You can try using the hidden field. Make the client side event on the OnclientClick event and try setting the value of hidden field, may be true or false depending on the condition.
And on the page load you can check the value of Hiidden field.
function click()
{
// set the hidden field here
}
And on the page load, simply check the value.
if(HiddenFieldName.Value=="true")
{
//perform the action
}
private bool button1WasClicked = false;
private void button1_Click(object sender, EventArgs e)
{
button1WasClicked = true;
}
if ( button1WasClicked== false)
{
//do somthing
}
I have two asp:Labels, the first of which is replaced with a few buttons and the second with a list of items.
I want to click on the buttons to filter the items.
The contents of the buttons are added programmatically by replacing the text with html and works fine.
asp:
<form id="form1" runat="server">
<asp:Label id="filters" runat="server" Text="Filters here"/>
<asp:Label id="itemList" runat="server" Text="List of items here"/>
</form>
resultant html of filters label:
<input type="submit" onclientclick="Load_Items(0)" runat="server" value="First"/>
<input type="submit" onclientclick="Load_Items(1)" runat="server" value="Second"/>
<input type="submit" onclientclick="Load_Items(2)" runat="server" value="Third"/>
relevant c#:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
Load_Items(0);
}
}
public void Load_Items(int filterType)
{
//code to load items (pseudo below)
for each row in list
if filterType = itemType
build string
replace second label with string
}
On page load everything happens just as I want it to with the contents being filtered by the first item (hence Load_Items(0)), and if I manually change the 0 to another number in Page_Load, it filters by the other types, but if I click the buttons which are programmatically added, nothing happens other than what looks like the page refreshing.
I know the post back check is working by adding a text replacement before and inside it.
I've also added an asp:button to make sure it's not something to do with the way the buttons are added as below (with some extra things recommended from searches):
<asp:Button runat="server" CausesValidation="False" onclientclick="Load_Items(2); return false;" text="Submit" />
So what could be the issue?
The OnClientClick property specifies the javascript to run in the browser when the button is clicked. Since you probably don't have a javascript function called Load_Items, this will generate a script error, and the button will then cause the form to post back.
The server-side Click event will fire on the server, but doesn't allow you to pass a parameter. You will only get the button instance and an empty EventArgs instance.
You might be better off using the Command event, combined with the CommandArgument property.
<asp:Button runat="server" CommandArgument="2" OnCommand="Load_Items" ...
The event handler would use the CommandArgument property of the CommandEventArgs to access the argument from the clicked button:
protected void Load_Items(object sender, CommandEventArgs e)
{
Load_Items(Convert.ToInt32(e.CommandArgument));
}
Well, that's the common problem which I think every asp.net developer deals some time. The common part of it, that asp.net event system doesn't work, as windows forms.
Page object, and all controls on that page, have lifecycle events, that are triggered during any request, even when it's from update panel.
As you create those controls by code, you have to keep in mind, that all events for those controls should work as part of Page object. That's why you have to create those object in Page_Init event, before all other control's event would be triggered.
Please also keep in mind that you have to create those controls as asp.net objects:
var btn = new Button();
But not by simply adding html markup. And you have to recreate them on each request, following that one, when they were created.
Please take a look on my another answer.
I was wondering if you guys could help me understand hidden fields, since I don't think I am getting them to work.
On the aspx page I have:
<asp:HiddenField ID="hidVal" value="" runat="server" />
On a button click I have a JavaScript function called
<button type="button" id="search" onclientclick="search_click()">Search</button>
With the function being
function search_click() {
document.getElementById('hidVal').Value = "1";
<% save(); %>
}
In aspx.cs I have a function that does this:
using (System.IO.StreamWriter file = new System.IO.StreamWriter(#"C:\Users\fgreene\Desktop\savedAdresses.txt", true))
{
file.WriteLine(hidVal.Value);
}
After clicking the button I look into the file and there is no change.
Is my approach correct or am I not understanding how this works?
Putting <% save(); %> in a JavaScript function in an aspx page causes save to be run when the page is built on the server, not when the surrounding JavaScript function is called on the client. At this point, the hidden field is empty, so your file gets a blank line written to it. When the user clicks the button, the hidden field is filled, but there's nothing to tell the server that this has happened.
What you need to do instead is something like:
// In your aspx, for the javascript function: remove the call to save,
// use the correct ID for the hidden field
function search_click() {
document.getElementById('<%= hidVal.ClientID %>').Value = "1";
}
// In your aspx in place of the button put
<asp:Button id="search" runat="server"
onclientclick="search_click(); return true;" onclick="search_click">
Search
</asp:Button>
// This results in a button that calls the javascript function on click, and
// then posts back to the server saying that the button has been clicked
// In your C#, this function gets called when the client posts back to
// say that the button has been clicked.
public protected void search_click(object sender, EventArgs e)
{
using (System.IO.StreamWriter file = new System.IO.StreamWriter(
#"C:\Users\fgreene\Desktop\savedAdresses.txt", true))
{
file.WriteLine(hidVal.Value);
}
}
You'll need to reference the client ID of the hidden field, which is probably not hidVal, as the actual client side ID generated in the HTML will be based on the parent control's naming container. There's two ways to fix this. First, you could make the client ID static on the control (which basically tells ASP.NET make the ID exactly what I said.):
<asp:HiddenField ID="hidVal" value="" ClientIDMode="Static" runat="server" />
Second, you can look up the ClientID property from the server when you generate your JavaScript:
document.getElementById('<%= hidVal.ClientID %>').Value = "1";
This would render out the actual client ID directly in the JavaScript code. Either approach is probably fine, but the second one would only work if the JavaScript is embedded directly in your ASPX file and not in a static .JS file.
Calling server side methods:
The second part of your question is about calling server side code when the button is pressed. You should do this by attaching an OnClick handler to your button:
<button runat="server" id="BtnSearch" onclientclick="search_click()" OnClick="btnSearch_Click">Search</button>
When the button is pressed, the page will be posted back and the btnSearch_Click event handler will be called. You'll then be able to handle any server side logic, as well as check the value of your hidden field. Hope this helps!
What you're trying to do is execute a server side function (save) via a client side call. This won't work as it is calling save() when the page first loads and then putting the return value (which is probably nothing) into the code where you put
<% save(); %>
Instead you need your button to fire the save function, but fire your javascript first. You do this by creating an asp:button (which renders as ) and then adding both an "OnClientClick" (for your javascript) and "OnClick" (for your server side function).
<asp:Button id="btnSearch" runat="server" OnClick="btnSearch_Click" OnClientClick="search_click()" text="Search" />
Then in your C# code you need the method to be named the same as the OnClick value:
protected void btnSearch_Click(object sender, EventArgs e)
{
using (System.IO.StreamWriter file = new System.IO.StreamWriter(#"C:\Users\fgreene\Desktop\savedAdresses.txt", true))
{
file.WriteLine(hidVal.Value);
}
}
The easiest way to create your server side function is to double click on the button in design view, as it will add the correct method call for you.
Hope this helps.
You can change hidden field value in both serverside and client side events.
Change value in client side
<script type="text/javascript">
function setvalue() {
document.getElementById('hidVal').value = "1";
}
</script>
<div>
<asp:HiddenField ID="hidVal" value="" runat="server" />
<br />
<asp:Button ID="Button1" runat="server" Text="Button" OnClientClick="setvalue();" />
</div>
Change value in serverside
<div>
<asp:HiddenField ID="hidVal" value="" runat="server" />
<br />
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />
</div>
protected void Button1_Click(object sender, EventArgs e)
{
hidVal.Value = "1";
}