How to check if a MaskedTextBox is empty from a user input?

Question

I'm using a MaskedTextBox, with the following short date Mask: "00/00/0000".
My problem is that I wanna know when the control is empty:

if (string.IsNullOrEmpty(maskedTextBox1.Text))
{
    DataTable dt = function.ViewOrders(Functions.GetEid);
    dataGridView2.DataSource = dt;
}

It's not working, when maskedTextBox1 looks empty (and I'm sure it is), the if statement doesn't detect that it is null or Empty.

Answer 1

You can simply use:

maskedTextBox1.MaskCompleted

Or

maskedTextBox1.MaskFull

properties to check if user has entered the complete mask input or not.

Answer 2

I know this is old but I would first remove the mask and then check the text like a normal textbox.

maskedTextBox.TextMaskFormat = MaskFormat.ExcludePromptAndLiterals;

//...Perform normal textbox validation

Answer 3

I just faced this problem. I Needed the Masked Value, but also needed send empty string if the user didn't introduced any data in one single step.

I discovered the property MaskedTextProvider.ToDisplayString so I use the MaskedTextbox with:

maskedTextBox.TextMaskFormat = MaskFormat.ExcludePromptAndLiterals;

BUT I always read the text from:

maskedTextBox.MaskedTextProvider.ToDisplayString() 

This way, if the user has not introduced text in the control Text property will be empty:

maskedTextBox.Text == string.Empty

And when you detect the string is not empty you can use the full text including literals for example:

DoSomething((maskedTextBox.Text == string.Empty) ? maskedTextBox.Text: maskedTextBox.MaskedTextProvider.ToDisplayString());

or

DoSomething((maskedTextBox.Text == string.Empty) ? string.Empty: maskedTextBox.MaskedTextProvider.ToDisplayString());

Answer 4

If you set the property maskedTextBox.TextMaskFormat = MaskFormat.ExcludePromptAndLiterals then the TypeValidationCompleted event validation will not work. To test if the short date maskedtextbox is empty you could just use:

        if (maskedTextBox1.Text == "  /  /")
        {
            ...;
        }

Answer 5

Did you try trim.

if(string.IsNullOrEmpty(maskedTextBox.Text.Trim())

Answer 6

What logic are you trying to accomplish with the if statement? As it is right know, you are saying: If the textbox is empty, set source of datagridview2 + to ViewOrder data. I'm not sure what your trying to do but I think you want the info to load if you have a date. to fix this all you have to do is add ! in the if statement which would make the if statement mean, if there is text in textbox then run code.

if( !(string.IsNullOrEmpty(maskedTextBox2.Text)))

Answer 7

In case of Telerik masked textbox which does not have MaskCompleted or MaskFull, a tricky solution would be this:

the mask always contain a charachter like this: "_" we check masked text box by this:

if (textbox1.Text.Contains("_"))
        {
            MessageBox.Show("Please enter the correct numbers!","Error",MessageBoxButtons.OK,MessageBoxIcon.Stop);
            return;
        }

if the text box is full, then it does not contain "_".

Answer 8

I believe the MaskedTextBox, (MTB), using the mask “00/00/0000” is an incorrect string to use for testing its emptiness. This is because the MTB is not like a normal textbox, and the short date mask must be used to determine its string value. Let’s assume you have a MTB name mskDateOfBirth on your form. In order to test its emptiness, a statement like the following is needed

if (mskDateOfBirth.MaskedTextProvider.ToDisplayString() == "__/__/____")
{
    // Do something when true
}   
else
{
    // Do something when false          
}

I have tested this out using Visual Studio 2019 and it works fine. Hope this is helpful.

Answer 9

If the empty value is " / /", declare a constant for it:

const string EmptyDateInput = "  /  /";

And then later you can repeatedly use it to compare:

if (maskedTextBox1.Text == EmptyDateInput)
{
}