This website completely moved to new platform. For latest content, visit

Search this Site

26 Apr 2013

convert textbox text to uppercase in c#

In this post we will see how to convert textbox text to upper case when it is entered . For this we will consider a example , suppose a textbox is taken for full name , then we should allow only characters/letters in it. And we want full name to be entered in upper case . for this we can validate a textbox such that the text entered in it should appear in uppercase automatically even if user entered a lowercase.


I am taking a textbox txtFullName on Form and a errorprovider. Now we are taking a keypress event of textbox txtFullName . The c# code is like this ..

private void txtFullName_KeyPress(object sender, KeyPressEventArgs e)

            if (!char.IsLetter(e.KeyChar) && Convert.ToInt32(e.KeyChar) != 8 && Convert.ToInt32(e.KeyChar) != 32)
                errorProvider1.SetError(txtFullName, "Only letters allowed");
                e.Handled = true;

                e.KeyChar = char.ToUpper(e.KeyChar);

According to the above code, textbox allows only letters , backspace , and space, And it converts the input text to uppercase even if user enters a lowercase letter .

If any other key like number or special character is entered by the user , the error provider will blink .