how to set error provide on prompt.

Question

hi..
I am using visual basic component in C#, now I want to set error provider message when input length is greater that four digits..

string str;
str = Interaction.InputBox("Please Enter Invoice No.", "Measurement Info", "", 260, 0xeb).Trim();
            if (str.Length > 4)
            {
              // errorProvider1.SetError(str.ToString(), "Values is Greater");

            }

please help me..

Vulpes · Answer

It's not possible to use the ErrorProvider with the InputBox because the InputBox isn't a control and it will have closed in any case before you can validate what the user has entered. If you don't want to do it as I've suggested then I'd either use a simple TextBox and handle its Validating Event (see http://msdn.microsoft.com/en-us/library/system.windows.forms.control.validating.aspx ) or write a custom dialog box which does allows you to validate the input before the dialog is closed.

Kanhialal kk · Answer

@ Vulpes : thanks sir But my requirement is some thing different.. as I click on button than Interaction.InputBox(msg+box); will appear and no doubt it appears but now if i put more than 4 digits in the box than set the error on that box of Interaction.InputBox(); by using visual studio component.

Suthish Nair · Answer

waw.. thanks Vulpes for sharing..

Vulpes · Answer

It's a class that exists in the .NET Framework as a whole not just Microsoft.VisualBasic.dll. It's normally used with textboxes and the like to indicate that the input is wrong. Check out the MSDN docs ( http://msdn.microsoft.com/en-us/library/system.windows.forms.errorprovider.aspx ).

Suthish Nair · Answer

I was confused with errorProvider. Is it a class exists in VB?

Vulpes · Answer

An ErrorProvider needs to be used in association with a control. The VB InputBox isn't a control and will have been closed in any case by the time the SetError() method is executed in your code. If you must use the InputBox for some reason then I'd pop up a MessageBox to tell the user there's an error and then pop up the InpuBox again so that the user can re-enter the invoice number: string str; while (true) { str = Interaction.InputBox(Please Enter Invoice No. Measurement Info  260 0xeb).Trim(); if (str.Length > 4) { MessageBox.Show(Invoice number cannot be more than 4 digits. Press OK to re-enter Measurement Info Error MessageBoxButtons.OK MessageBoxIcon.Error); } else { break; } }