Validating multiple textboxes using errorprovider

c#, winforms

Solution

Yes, there is.

First, you need to obtain all the text boxes in form of a sequence, for instance like this:

var boxes = Controls.OfType<TextBox>();

Then, you can iterate over them, and set the error accordingly:

foreach (var box in boxes)
{
    if (string.IsNullOrWhiteSpace(box.Text))
    {
        errorProvider1.SetError(box, "Please fill the required field");
    }
}

I would recommend using `string.IsNullOrWhiteSpace` instead of `x == ""` or + `string.IsNullOrEmpty` to mark text boxes filled with spaces, tabs and the like with an error.

Problem

I have 10 textboxes, now i want to check that none of them are empty when a button is clicked. My code is : ``` if (TextBox1.Text == "") { errorProvider1.SetError(TextBox1, "Please fill the required field"); } ``` Is there any way that I can check all the textboxes at once, rather than writing for every individual?

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