public static Expression <Func <TSource, bool> > And <TSource>(this Expression <Func <TSource, bool> > a, Expression <Func <TSource, bool> > b)
{
Type typeFromHandle = typeof(TSource);
ParameterExpression parameterExpression = Expression.Parameter(typeFromHandle, "root");
Expression left = ParameterExpressionReplacer.Replace(a.Body, parameterExpression);
Expression right = ParameterExpressionReplacer.Replace(b.Body, parameterExpression);
BinaryExpression body = Expression.And(left, right);
return(Expression.Lambda <Func <TSource, bool> >(body, new ParameterExpression[]
{
parameterExpression
}));
}
public static LambdaExpression And(this LambdaExpression a, LambdaExpression b)
{
if (a == null)
{
return(b);
}
if (b == null)
{
return(a);
}
Type rootType = a.Parameters[0].Type;
var memberParam = Expression.Parameter(rootType, "root");
var aNewBody = ParameterExpressionReplacer.Replace(a.Body, memberParam);
var bNewBody = ParameterExpressionReplacer.Replace(b.Body, memberParam);
var newBody = Expression.And(aNewBody, bNewBody);
var lambda = Expression.Lambda(a.Type, newBody, memberParam);
return(lambda);
}
