i have a page a three buttons, when user clicks 1st control i want to display 1st user control, for button2 second user control and so on... how can i achieve this in page_init as we dont knw which button got clicked
you can find the button ID with this trick in Page_Init event
string buttonID = Request["__EVENTTARGET"].ToString();
In buttonID in buttonID variable you will find the client ID of the button..
It depends on how you want to display them.
It is easier to have the controls hidden when not needed and only visible when required.
If you want to add them dynamically the easiest way to add them is to add the control to a placeholder when you need them.
eg
ASP
<asp:PlaceHolder id="myPlaceHolder" runat="server"></asp:PlaceHolder>
Code behind (C#)
myControl = new UserControl();
myPlaceHolder.Controls.Add(myControl);
But you also need to remember that to be able to access the control on postback you need to re-add it on submit/postback.
Related
I have the following situation:
I coded a aspx app c#, the user has 4 dropdownlists, one textbox and two buttons (cancel, save) in a page. I need the user to be remembered to save any changes to the textbox before allowing him to change the index of any dropdownlist. So, if the user changes the textbox value, he only have the option to cancel or save those chhanges. If he tries to do something else, like changing the index of a dropdownlist, I need to cancel this event and give him a message to save or cancel before do this.
I've tried many ways, but they all seem amatours to me and give lots of colateral efects. Is there any decent/elegant way to do this?
Create a custom validator for the TextBox. In the DropDownList's SelectedIndexChanged event handlers check the status of the TextBox and set the validator's args.IsValid property appropriately - you can notify the user via the TextBox CustomValidator ErrorMessage property to click Save if the value of the TextBox has changed.
I have a webpage. I show records from table, lets say, students in my page. I query all the students and show them in grid. I want to use a textbox for filtering the datagridview results. For example if the user types a in the textbox the grid will show only the students who has "a" in his/her name. I want to refresh the grid at the same time while textbox is being edited.
i have set the autopostback property of textbox to true, and i refresh the grid in textbox's textchanged event.But the textchanged event fires only after the textbox loses focus. How can I make it fire after user types just one character ? thanks.
You have to use the onKeyDown event. However, I'd advise you to use ASP.NET AJAX or jQuery to load the results with Ajax.
Here is one example from asp.net: http://www.asp.net/ajaxlibrary/AjaxControlToolkitSampleSite/AutoComplete/AutoComplete.aspx
Another one, from Code project:
http://www.codeproject.com/Articles/38803/Google-Like-Search-TextBox
You might want to show some your present code, if there is a particular method you want to go with for this. Otherwise your going to get a people telling you the way they would do it.
Does it look something like this right now?
<asp:Textbox id="myTextbox" runat="server" onChange="txtChanged" AutoPostBack="true"/>
public void txtChanged(object sender, EventArgs e)
{
//Get text from textbox
string text = ((TextBox)sender).Text;
//Do what ever it is you want to do to edit the text
text = text.ToUpper();
//Update the other textbox with this text
txtMyText2.Text = text;
}
I think the best and most clean way is to use Rad Controls, here is an example on how to do it:
http://demos.telerik.com/aspnet-ajax/controls/examples/integration/gridandcombo/defaultcs.aspx?product=grid
The event TextChanged only fires when you send a request to server. If you wanna launch an event or make a function when the text inside textbox changes, use an OnKeyDown event (right with Schiavini).
You can use PicNet to do this in the Client instead of the Server for a better User experience. You can find it here http://www.picnet.com.au/resources/tablefilter/demo.htm Remember that the Gridview is rendered as a HTML table, therefore you can freely use this jQuery plugin.
Good luck!
I am working on ASP.NET application where I am reusing a user control. The user control contains a checkbox and bunch of other controls. I want to display all the controls inside the user control on all the pages but on one single page I want to hide the checkbox.
I was thinking that I can use the databind methods and see if I am on the "pagex" then hide the checkbox. Is there any other way to solve this problem?
If you have access to the code for the control you should be add a new property to the control for hiding/showing the checkbox and then just pass in the property depending upon what page you are on. You'd have to pass in the show/hide property on the load event of the page.
Do you have access to the code??
I would specify a parameter in the code behind for your ascx file. Example:
public bool HideCB = false;
THen when you put your User Control on your aspx page do this:
<uc:TestControl id="TestControl" runat="Server" HideCB="true" />
This way you can do a check on if(HideCB) to determine if you want to make it visible or not.
I have 3rd party user control (a captcha control), which has a captcha image, a text box within it.
I am using the above user control in my webpage. I have a 3 submit buttons on my webpage (Validate Captcha, Submit Page, Add User). When I click the Validate Captcha submit button using the mouse, I am validating whether captcha is empty and showing a javascript alert.
The problem comes when I enter the valid captcha text in the textbox and hit enter key when the cursor is in the textbox. The page just refreshes. I am unable to add keypress event to textbox and call Validate Captcha button event as I am using the 3rd party user control which I cannot modify.
Also, Page.ClientScript.RegisterHiddenField(...) will not work in my case as I have two other submit button inside the same page.
Only option left is to enclose these in panels and set default button.
Please let me know if anyone has any better options for achieving this.
Greetings! I too use alot of third party controls. The thing to remember about these controls, it that in the end they just emit HTML. This means you can use the DOM to access and attach event handlers such as onKeyPress. The trick is to identify how your control creator named the control you are looking for, in this case a {textbox}. The easiest way to achieve this is to simply run the page and view the page source. It is there that you can find the name as it is rendered and sent to the browser, after that all you have to do us use document.getElementByID to get the object and setup your handler
Example:
<script>
//Place this AFTER your textbox control is declared in the HTML
//Get the textbox
var textbox = document.getElementById('nameOfRenderedControlHere');
//Assign the event handler and function you want it to call
textbox.onclick = function() { validateCaptcha(); };
function validateCaptcha()
{ //Do your Stuff here }
</script>
That should be it..havent tested, let me knwo if you run into questions.
Put the captcha in its own <asp:Panel> and add a DefaultButton property for the panel with the ID of the captcha's submit button.
I've a following requirement for my asp.net page:
User can add a textbox dynamically on a page A by clicking on link "Add a new category" hyperlink
He clicks submit button on page A and gets redirected to page B.
When he clicks on page A link from this page, the textboxes that he added should be persisted.
Can someone help me with the code on this?
Appreciate your help!
In the ButtonClick Method write.
TextBox tb = new TextBox();
Parent.Controls.Add( tb );
The Parent is the control you want to add the textbox to, for instance a panel.
You can also look at this resource.
Hope it helps.
Adding a user control dynamically is simple. But in this case, I don't think you need to do that, instead you should look at creating a repeater with a textbox inside it, and when the user clicks Add Category, add one item to the repeater datasource.
This way you can handle both control creation and state persistence at the same time.
dealing with dynamic user controls can be a pain in the ass.
as a rule of thumb i follow, whenever you create a dynamic user control, then you must set it's ID so ASP.net can reallocate it on post back, and to keep the controls values after post back you should reload your user controls on Page_Init event.
hope this helps.
Dynamically creating Textboxes:
suppose you have page like this
when you enter '1' in textbox and click on ADD button,output will be like display one textbox
below..
i have designed like this,
i have one textbox and placeholder for displaying dynamic textboxes..
double click on Add button...in btnadd_click,you have to write the following code
protected void btnadd_Click(object sender, EventArgs e)
{
int i;
for (i = 0; i < Convert.ToInt32(txtno.Text); i++)
{
TextBox txtbox = new TextBox();
phtxt.Controls.Add(txtbox);
phtxt.Controls.Add(new LiteralControl("<br>"));
}
}
debug it... and the output is,
As others have stated adding the text box dynamically is fairly straight forward, just create the Textbox and add it to the controls collections wherever you need it to show up. You then need to store the information that this user gets this additional text box. Assuming that this is meant for long term, you will need to store this information in your backend store. Whenever you are constructing the page you will need to read the store information first to see what textboxes to create.
I would suggest doing it as follows. In the Onload event, if you have not done so before, load the dynamic information from your DB. Add any necessary controls to the page and store this information in viewstate. On any subsequent postbacks, read the information from viewstate to add the additional controls. This will save you from having to read constantly from the database on each postback.