Develop Reference

Control.Attributes.Add doesn't work for check box

I have created dynamic checkbox with ID="chk" and I want to apply inline style to it. I tried
chk.Attributes.Add("style","opacity:1");
But it doesn't work as expected. It created span around check box and applies style to that.
But it works
chk.InputAttributes["style"] = "opacity:1";
But former works fine for TextBox. Why this complexity for different controls?
Update
As un-lucky answered, it is just an alternative that buries my real question i.e. Why this complexity for different controls?. Lets forget about style, think of any other atrribute. Why check box is different when it comes to Attribute.Add?

To add styles you have to try Style property instead for Attributes Following code will help you:
chkBox.Style.Add("opacity", ".3");
You can also try like this:
chkBox.Style["width"] = "70px";
chkBox.Style["height"] = "70px";

ASP.Net renders two <input> elements for checkboxes to overcome the fact that an unchecked checkbox is not POSTed.
I guess the easier approach is to assign CSS classes in code, and adjust your CSS to deal with the HTML details.

Compare multiple textbox - Make sure 1 is entered

In my Content page I have 4 different TextBox's which is used to enter phone number - Mobile, Office Phone, Office Mobile & Other. I have RegularExpressionValidator for each.
I want to make sure atleast one of the above 4 textbox's has entered a value. I didn't find any example or article on net showing this situation. One way I think is in Submit button click, before Page.IsValid call, call a function that checks that one of the control has valid value. If the function returns false, show MessageBox. Is their any other way using Validators or so to comfirm that one textbox out of 4 has a valid value.
What can be the best way to achieve this ?
Any help is highly appreciated.
Thankss

You can create a Custom Validator in ASP.NET.
This post should help you out.
asp.net required field validator for at least one textbox contains text

How to build a "word-by-word" autocomplete in WPF?

I already did some research and ended up with several autocomplete boxes which have one thing in common: they all match the whole expression which has been entered. Sometimes, they seem to be easily expandable, but at the end, they aren't.
However, I need a Textbox which allows the user to enter a word (e.g. "tag1"), displays a popup with some suggestions based on this single word, accept the suggestion with the return key and type in a new word (e.g "tag1 tag2") in the same textbox, with the popup popping up again. (I like the way CintaNotes handles this)
I need this for a tagging interface. It's often faster for the user to write the tags into a simple box, but sometimes, he needs assistance. This is what the autocomplete is for.
I've found some results, which don't work for my purpose (imho):
http://www.wpfpedia.com/item/details/743/wpf-autocomplete-textbox-control
http://www.codeproject.com/KB/WPF/WPF_Autocomplete.aspx
http://www.codeproject.com/KB/WPF/autocomplete_textbox.aspx
http://weblogs.thinktecture.com/cnagel/2011/01/autocomplete-textbox-with-wpf.html
Btw, I really like the way the Tag-Box for SO operates.
Does anyone have an idea? Is there a "out-of-the-box" - solution somewhere, which suits my needs but I didn't find? Or do I have to build one myself?
Thanks! :)

I think you mean a textbox which autocomplete for multiple words.
Like TokenizedTexbox on WPF Extended Toolkit.
this is the page: http://wpftoolkit.codeplex.com/wikipage?title=TokenizedTextBox&referringTitle=Home

Probably you would need to create your own Dictionary object of Key and Value pairs and hook that Dictionary to the textbox events and popup a suggestions dialog that displays the Value(s) from your Dictionary

Check this implementation out: http://code.google.com/p/kocontrols/downloads/list
You may inject your own Search algorithm and your own converter which converts the selected element to text, which you display in the TextBox. You will have to modify it slightly but I think that you might be able to solve your problem by basing your control on this implementation.
I never thought about this type of use case.
Can't you use different textboxes for the different tags? Something similar to how goole code does it?

If you have time, you can use the RichEditControl or TextBox and apply the same pattern used in Intellisense engine or Code Completation enabled editors: Hook the text changes events, Recogize context (last/current word) and display the options list on popup control. And optionally, on commit (detect acceptation or space key), apply the format to the word.

Custom validatior in ASP.net

I'm working on an ASP.NET/C# app.
I have 2 text boxes and I need to validate if the input text for both of them are not both null
ex:
if(string.IsNullOrEmpty(TextBox1.Text) && string.IsNullOrEmpty(TextBox2.Text) )
//FAIL!!!
else
// OK!
that is, at least one txtBox has values
I was planning on using a custom validator but it seems that the validation function only gets called when something is written on the textBox i'm using has the 'control to validate'. Now, that doesn't work for me since I want to show an error message when both text boxes are empty. Is there a way to make the validation function to be called with, for example a postback? Or is there any other better approach to this case than the custom validator?
tks

If you set the 'ControlToValidate', then the validator will not fire if that control is empty. However, for a CustomValidator you can leave that empty so it will always fire.

Because the built-in validators only analyze the state of their own controls, you are forced to go with a CustomValidator for this functionality. I don't know of any better approach that still uses ASP.NET server-side validators. As Hans said, be sure to leave ControlToValidate empty, and then do the validation as in your code sample.

ASP.NET Multiple Field Validation

In ASP.NET 2, I've used Field Validators, and RequiredField validators, but I'm unsure of how to handle a case like this.
I have two check boxes on a page, and I need to be sure that at least one of them is set. So, if you look at in binary, it can be 01, 10 or 11, but it can not be 00. My question is, what the best way to do this with checkboxes?
Can the normal ASP Validators handle this, or would I need to create an integer value like mentioned above, hidden somewhere and use a RangeValidator do a test to make sure THAT value is never zero?

Worst case you can write a CustomValidator the can do whatever you like. Sounds like what you need is along the lines of:
isValid = Check1.Checked | Check2.Checked

Use CustomValidator

This control (written by me) supports CheckBox and CheckBoxList:
http://www.codeproject.com/KB/validation/AtLeastOneOfValidator.aspx
Just add it to visual studio, drop it on your page, and add your checkboxes to it's Controls list. It will work like any other validator control.

Custom validator is the obvious solution. Also, when using a custom validator you should also check for validity on the server side just in case the javascript fails due to some reason.
P.S.: Don't always trust what the client(browser) sends you.

Here is an article I wrote regarding this exact issue. I also wanted to validate multiple controls which was easy using the CustomValidator but one of the issues I was not happy about is that if you corrected the validation issue the error did not go away until you posted back.
I figured out a way to hide the error message and revalidate and wrote a small blog entry about it. Check it out and see what you think.
http://coding.infoconex.com/post/ASPNET-CustomValidator-that-validates-multiple-controls-using-both-Server-Side-and-Client-Side-scripting.aspx