Construct LambdaExpression for nested property from string

Do you mean:

static LambdaExpression CreateExpression(Type type, string propertyName) {
    var param = Expression.Parameter(type, "x");
    Expression body = param;
    foreach (var member in propertyName.Split('.')) {
        body = Expression.PropertyOrField(body, member);
    }
    return Expression.Lambda(body, param);
}

For example:

class Foo {
    public Bar myBar { get; set; }
}
class Bar {
    public string name { get; set; }
}
static void Main() {
    var expression = CreateExpression(typeof(Foo), "myBar.name");
    // x => x.myBar.name
}

?