Question

I have a method that accepts an Expression<Func<T, bool>> as a parameter. I would like to use it as a predicate in the List.Find() method, but I can’t seem to convert it to a Predicate which List takes. Do you know a simple way to do this?

public IList<T> Find<T>(Expression<Func<T, bool>> expression) where T : class, new()
{
    var list = GetList<T>();

    var predicate = [what goes here to convert expression?];

    return list.Find(predicate);
}

Update

Combining answers from tvanfosson and 280Z28, I am now using this:

public IList<T> Find<T>(Expression<Func<T, bool>> expression) where T : class, new()
{
    var list = GetList<T>();

    return list.Where(expression.Compile()).ToList();
}

Answer 1

Func<T, bool> func = expression.Compile();
Predicate<T> pred = t => func(t);

Edit: per the comments we have a better answer for the second line:

Predicate<T> pred = func.Invoke;