Search Button Enabled/Disabled in VB.net

Question

0.00/5 (No votes)

See more:

Hello, I have a small problem but don't know how to solve it.

I have 3 textboxes, one combobox, one maskedtextbox and a button.

I have successfully implemented a code, where when all the textboxes, combobox and maskedtextbox are blank, the button is disabled. Good!

However, when a person wil fill one of these fields, he can erase a the word/character by the backspace and delete key or simply erase it with his mouse, so I want that if the user does this, the button disabled again. I mean when he will insert a character/word and erase it with his mouse or keyboard by using the backspace and delete key, the button must be disabled again.

Help, thank you.

Posted 28-Apr-11 0:27am

555336

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Wayne Gaylard · Accepted Answer · 2011-04-28T01:00:00

Solution 1

What you need to do is implement a function which gets called in each control's Leave event.
Something like this

VB

Private Sub TextBox1_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles TextBox1.Leave, TextBox2.Leave, TextBox3.Leave, MaskedTextBox1.Leave, ComboBox1.Leave
        DisableButton()
    End Sub
    Private Sub DisableButton()
        'Disable button here if all controls empty
    End Sub

Hope this helps

Posted 28-Apr-11 1:00am

Wayne Gaylard

Comments

555336 28-Apr-11 7:08am

Nope does not work. I forgot to say that I have a pretext also on my textbox only.

Wayne Gaylard 28-Apr-11 7:15am

Can you let me know what didn't work. The Leave event will be fired whenever the user leaves each control. Once the user has left the control you need to use this event to check and see if what the use entered hass valid or has erased what was in the control.

NuttingCDEF 28-Apr-11 7:21am

Probably need to handle the TextChanged events (fired whenever text changes, not just when focus moves away from the control). This works for pasting text / deleting text with the mouse / context menus as well as keystrokes.

I frequently write a single method UpdateControls that gets called any time any text or anything else changes in a form that updates button states etc. depending on current control values (so check for your pretext as well as blanks). Just watch that you make it lightweight as otherwise the user interface might get quite sluggish.

Wayne Gaylard 28-Apr-11 7:29am

That means running a check after each key entry/deletion, which is OK I guess, if the user changes something and doesn't leave the control.

555336 28-Apr-11 7:27am

B

Wayne Gaylard 28-Apr-11 7:33am

I thought you said you already had the method to disable the button. You still need to call this method from either the TextChanged event as NuttingCDEF said or from the Leave event as I described.

555336 28-Apr-11 7:38am

Yes I did implement my code for buttons. But as I said, when the user erase or delete with keyboard or mouse, the button does not return disabled as the field is blank when he does that.

The name checkboxes can be changed, I changed mine.

Sandeep Mewara 28-Apr-11 9:53am

5 for answer, effort and discussion