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How to create own DataColumn Aggregate function

I want to create my own Aggregate function to be used in the
DataColumn.Expr ession property.

So for example,
DataColumn col = new DataColumn("foo ", typeof(String)) ;
col.Expression = "my_custom(Chil d.Test)";

Anyone done this before? Any suggestions on where to start?

thanks

Mar 15 '07 #1
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