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Data binding and Null Values

When you bind a text box to a field that contains null values the text box
displays an empty string. Great!

My Database field is an integer and I want an empty text box to represent a
NULL value. However the EndEdit event on the datarow returns the error The
input string was in an incorrect format

I have failed to find a way to either trap the empty string in the
rowchanging event and turn it into DBNULL or to programatically manipulate
the value in the field to DBNull.Value when a keypress results in no thext
left in the Textbox.

How? Please, can I comunicate a NULL value back to the datarow with a
databound text box?

Regards

Ben Reese
Jul 25 '05 #1
1 2421
Handle the Parse event of the Binding on your textbox. In it, you can return
dbnull.value if the textbox contains an empty string.

"Ben Reese" <Be******@discu ssions.microsof t.com> wrote in message
news:F1******** *************** ***********@mic rosoft.com...
When you bind a text box to a field that contains null values the text box
displays an empty string. Great!

My Database field is an integer and I want an empty text box to represent
a
NULL value. However the EndEdit event on the datarow returns the error The
input string was in an incorrect format

I have failed to find a way to either trap the empty string in the
rowchanging event and turn it into DBNULL or to programatically manipulate
the value in the field to DBNull.Value when a keypress results in no thext
left in the Textbox.

How? Please, can I comunicate a NULL value back to the datarow with a
databound text box?

Regards

Ben Reese

Jul 25 '05 #2

This thread has been closed and replies have been disabled. Please start a new discussion.

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