Create an Expression using reflection

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The code to create the expression dynamically would be like this:

ParameterExpression parameter = Expression.Parameter(typeof (GoalsModelUnitOfWork), "i");
MemberExpression property = Expression.Property(parameter, "AcademicCycles");

var queryableType = typeof (IQueryable<>).MakeGenericType(typeof (AcademicCycle));
var delegateType = typeof (Func<,>).MakeGenericType(typeof (GoalsModelUnitOfWork), queryableType);

var yourExpression = Expression.Lambda(delegateType, property, parameter);

The result will have the desired type, but the problem is that the return type of Expression.Lambda() is LambdaExpression and you can’t perform a type cast to Expression<Func<...>> to pass it as parameter to your setup function because you don’t know the generic type parameters for the Func. So you have to invoke the Setup method by reflection, too:

this.GetType().GetMethod("Setup", yourExpression.GetType()).Invoke(this, yourExpression);

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