Guided exercise – constructing and manipulating expression trees

To help you understand expression trees better, let’s look at this exercise. Our goal is to create an expression tree representing the lambda expression (x, y) => x * y. This represents a multiplication operation. Afterward, we’ll compile and invoke this expression, effectively performing the multiplication of two numbers.

Let’s break down the steps:

1. Define the parameters for the lambda expression. These are x and y, which are both of the int type:

   ParameterExpression x = Expression.Parameter(typeof(int), "x");
   ParameterExpression y = Expression.Parameter(typeof(int), "y");

2. Construct the body of the lambda expression. This is the x * y operation:

   BinaryExpression body = Expression.Multiply(x, y);

3. Now, we combine the parameters and the body into a lambda expression:

   Expression<Func<int, int, int>> multiplyExpression = Expression.Lambda<Func...