Question

I have made the following class to avoid the repetition if else code , again and again :

public class Error 
{

    private ErrorProvider errProvider;


    public void SetError(Control control, string value)
    {

        errProvider = new ErrorProvider();

        if (control.Text.Trim().Length == 0)
        {
            errProvider.SetError(control, value);
        }
        else
        {
            errProvider.SetError(control, "");

        }

    }


}

and validation on textbox code is

private void textBox1_Validating(object sender, CancelEventArgs e)
    {

            erp.SetError(textBox1, "Please Enter Name");

    }

1. After typing the text in texbox, as I press enter, it working fine;
2. Without Entering any thing in textbox, as I press Enter , it also
   working fine means Waring red icon appears; BUT
3. after warning, as I press tab after entering text in textbox ,
   warning Icon does not disappear , it sould be removed.

without class it is working fine with the same code

update?

Answer 1

Use Field Initializer

private readonly ErrorProvider errProvider = new ErrorProvider();

You should use Field Initializer for errProvider, because every time calling Error.SetError, ErrorProvider will be constructed, and a constructed ErrorProvider will not only no disappear but also be just layered.

---

[updated]

public class Error
{
    private readonly ErrorProvider errProvider = new ErrorProvider();
    public void SetError(Control control, string value)
    {

        if (control.Text.Trim().Length == 0)
        {
            errProvider.SetError(control, value);
        }
        else
        {
            errProvider.SetError(control, "");
        }
    }
}