Change Mask of MaskedEditExtender?

Is it possible to change the Mask of a MaskedEditExtender without posting back?

I have a field for telephone number in format "999-9999"

When the checkbox beside the textbox is checked, it should change to "(999)-999-9999" format, and should go back to previous format when unchecked.

Hi Seven21,

Try out this.

if (CheckBox1.Checked)

{

TextBox1_MaskedEditExtender.Mask ="999-9999";

}

else

TextBox1_MaskedEditExtender.Mask ="(999)-999-9999";