Problems with TextBox control

Hi,
I'm new here and new to development.  I have a problem that I could really use help on.
I added a textbox to a web form called unitPriceTextBox.
I have some simple code:
aDecimalNumber = Decimal.Parse(unitPriceTextBox.Text);
anIntegerNumber = Convert.ToInt32(unitPriceTextBox.Text);
It was working fine yesterday, but now I am receiving a Format Exception error... Input string was not in a correct format.
Does anyone have any idea?  It's driving me crazy.  BTW, I type 1 in the textbox... so I know for sure it's a number.



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