How to use an Iif Statement in an Expression

Question

I have this line of code in c# I keep getting this error=> Syntax error: Missing operand before '&' operator.

Find below is my code

ds.Tables[0].Columns.Add("RESULTS").Expression = "Iif(((ActualWeight >= (.96 * TargetWeight)) && (ActualWeight <= (1.04 * TargetWeight))),[GOOD] )";

Answer 1

You are missing the false part of the expression as well as Iif is not syntactically correct. so try something like this

ds.Tables[0].Columns.Add("RESULTS").Expression = "IIF(((ActualWeight >= (.96 * TargetWeight)) And (ActualWeight <= (1.04 * TargetWeight))),[GOOD], [BAD])"

Answer 2

DataTable Expressions are more like VB than C#. The && is not supported by And is:

ds.Tables[0]
  .Columns
  .Add("RESULTS")
  .Expression = "Iif(((ActualWeight >= (.96 * TargetWeight)) And (ActualWeight <= (1.04 * TargetWeight))),[GOOD],null)"; 

Note that I also added a false condition to complete the expression.