This exception is thrown when incorrectly attempting to create or access a DataRelation object. For example, if you attempt to remove a DataRelation when a corresponding ForeignKeyConstraint exists on a table, or if you try to specify DataRelation parent-and-child columns with incompatible data types or in tables from different DataSet objects, this exception is thrown. public class InvalidConstraintException : DataException { // Public Constructors public InvalidConstraintException ( ); public InvalidConstraintException ( string s ); // Protected Constructors protected InvalidConstraintException (System.Runtime.Serialization.SerializationInfo info , System.Runtime.Serialization.StreamingContext context ); } HierarchySystem.Object System.Exception(System.Runtime.Serialization.ISerializable) System.SystemException DataException InvalidConstraintException |