i used the tableadapter wizard to gen the form.
for table a, and table b. of which a and b have relationship

now in form a, i try to make a manually lookup button that seeks value from
b and fill it in into the form a (table a)'s textbox, if user dodn't lookup
value, then it will set the text box to "",

but problems comes up, while it save, it said it had voliate the
constraints,
i know there had some problems on the insertion statments for that table
adapters? i.e. insert "" into a, insert NULL into a, which i want the one
behind, and the genernated code seems used the first one.

how can modifiy this ?
thx

Gary,

Are you sure of that that "" in the textbox is the reason of your problem.

Can you show some code. (If you not have binded it than it sounds strange
for me).

By the way, in my opinion are questions without language.vb code about
adonet more for the newsgroup.

microsoft.public.dotnet.framework.adonet.

Feel free where you want to post this kind of questions by the way.

Cor

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