How to create an Expression AND clause from two expressions

I am trying to create a where clause for my view using LINQ.

I was able to create single column where clause and I would like now to create multiple column where clauses..

I have seen code to implement in .Net 4 and above, but since I have to use .Net 3.5, I need a quick work around for this. so what I am trying to do is....

 Expression leftexp = {tag=>((tag.id=2)||(tag.id=3))}
 Expression rightexp = {tag=>((tag.uid="MU")||(tag.uid="ST"))}

from these two expressions i would like to create

 BinaryExpression be = {tag=>((tag.id=2)||(tag.id=3))} && 
                       {tag=>((tag.uid="MU")||(tag.uid="ST"))}

something like this which i could pass to my where clause in LINQ.

I tried to use Expression.And(leftexp,rightexp)

but got the error..

The binary operator And is not defined for the types
'System.Func2[WebApplication1.View_MyView,System.Boolean]' and 'System.Func2[WebApplication1.View_MyView,System.Boolean]'.

Expression is new for me and might have looked at too much of code so a bit confused to how to go about doing this... would really appreciate if you could point me in the right direction.

c# expression-trees

Edit Report

Rewriting expressions has been made easy with the addition of ExpressionVisitor to BCL. With some helpers the task gets almost trivial.

Here's a visitor class I use to apply a delegate to the tree nodes:

internal sealed class ExpressionDelegateVisitor : ExpressionVisitor {

    private readonly Func<Expression , Expression> m_Visitor;
    private readonly bool m_Recursive;

    public static Expression Visit ( Expression exp , Func<Expression , Expression> visitor , bool recursive ) {
        return new ExpressionDelegateVisitor ( visitor , recursive ).Visit ( exp );
    }

    private ExpressionDelegateVisitor ( Func<Expression , Expression> visitor , bool recursive ) {
        if ( visitor == null ) throw new ArgumentNullException ( nameof(visitor) );
        m_Visitor = visitor;
        m_Recursive = recursive;
    }

    public override Expression Visit ( Expression node ) {
        if ( m_Recursive ) {
            return base.Visit ( m_Visitor ( node ) );
        }
        else {
            var visited = m_Visitor ( node );
            if ( visited == node ) return base.Visit ( visited );
            return visited;
        }
    }

}

And here are the helper methods to simplify the rewriting:

public static class SystemLinqExpressionsExpressionExtensions {

    public static Expression Visit ( this Expression self , Func<Expression , Expression> visitor , bool recursive = false ) {
        return ExpressionDelegateVisitor.Visit ( self , visitor , recursive );
    }

    public static Expression Replace ( this Expression self , Expression source , Expression target ) {
        return self.Visit ( x => x == source ? target : x );
    }

    public static Expression<Func<T , bool>> CombineAnd<T> ( this Express


                        
                        
                            answered 2012-10-04T21:58:16.880

How to create an Expression AND clause from two expressions

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