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Need help with validating an alphanumeric string within a textbox control.

Posted By:      Posted Date: August 28, 2010    Points: 0   Category :.NET Framework
Hi everyone,I am developing a simple WinForms app for a presentation next week and need to validate that a particular string in a particular textbox is alphanumeric.  I have included the code from the button click event handler below: // Alphanumeric private void btnValidate4_Click(object sender, EventArgs e) { try { if (txtAlphanumeric.Text == "") MessageBox.Show("Please enter an alphanumeric string before clicking the 'Validate' button.", "Whoa there, pardner!!", MessageBoxButtons.OK, MessageBoxIcon.Information); else { Regex rgxAlphanumeric = new Regex("^[a-zA-Z0-9]*$"); Match alphaNumericMatch = rgxAlphanumeric.Match(txtAlphanumeric.Text); if (!alphaNumericMatch.Success) MessageBox.Show("The string supplied does NOT match the specified pattern.", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error); else { MessageBox.Show("The supplied string matches the specified pattern.", "Success!", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

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