3
考虑下面的代码这项工作...我怎样才能让深性质
class Program {
static void Main(string[] args) {
Foo foo = new Foo { Bar = new Bar { Description= "Martin" }, Name = "Martin" };
DoLambdaStuff(foo, f => f.Name);
DoLambdaStuff(foo, f => f.Bar.Description);
}
static void DoLambdaStuff<TObject, TValue>(TObject obj, Expression<Func<TObject, TValue>> expression) {
// Set up and test "getter"...
Func<TObject, TValue> getValue = expression.Compile();
TValue stuff = getValue(obj);
// Set up and test "setter"...
ParameterExpression objectParameterExpression = Expression.Parameter(typeof(TObject)), valueParameterExpression = Expression.Parameter(typeof(TValue));
Expression<Action<TObject, TValue>> setValueExpression = Expression.Lambda<Action<TObject, TValue>>(
Expression.Block(
Expression.Assign(Expression.Property(objectParameterExpression, ((MemberExpression)expression.Body).Member.Name), valueParameterExpression)
), objectParameterExpression, valueParameterExpression
);
Action<TObject, TValue> setValue = setValueExpression.Compile();
setValue(obj, stuff);
}
}
class Foo {
public Bar Bar { get; set; }
public string Name { get; set; }
}
class Bar {
public string Description{ get; set; }
}
因为我访问浅属性DoLambdaStuff(foo, f => f.Name)
调用工作正常,但调用DoLambdaStuff(foo, f => f.Bar.Description)
失败 - 虽然创作的getValue
函数工作正常,创建setValueExpression
失败,因为我试图访问该对象的深层属性。
任何人都可以请帮我修改这个,这样我就可以创建setValueExpression
深的属性以及浅?
谢谢。
谢谢,这似乎正是我所期待的。 – 2010-05-16 11:15:06