lambda表达式作为属性(lambda Expression as a property)

 我有一个工作设置，它不是强类型的，而是依赖于反射。 
 
 说，我有一堂课 
 
class Person{

    public string FirstName {get ; set;}
    public string LastName {get; set;}
    public int Age {get; set;}
    ...  
    // some more public properties
}
 
 和 
 
class CellInfo {
     public string Title {get; set;}
     public string FormatString {get; set;}
}
 
 我有这样的字典 
 
Dictionary<string, CellInfo> fields = new Dictionary<string, CellInfo>();
fields.Add("FirstName", new CellInfo {Title = "First Name", FormatString = "Foo"});
fields.Add("LastName", new CellInfo {Title = "Last Name", FormatString = "Bar"});
 
 这是一个简单的字典，其中包含属性名称和一些关于它们的信息 我将字典传递给处理Person实例的另一个模块，而我也是如此 
 
Dictionary<string, CellInfo> fields = SomeMethodToGetDictionary();
foreach(Person p in someCollection)
{
    foreach(var field in fields)
    { 
       object cellValue = type(Person).GetProperty(field.Key).GetValue(p, null);
       // use cellValue and info on field from field.Value somewhere.
       ...
    }
 }
 
 这种传递字段名称和使用反射的字符串的方法可行，但我想知道是否有强制类型的方法。 
 
 我想到的是有一个存储linq表达式的属性，就像这样 
 
fields.Add("FirstName", new CellInfo 
                   {
                      Title = "First Name", 
                      FormatString = "Foo",
                      EvalExpression = p => p.FirstName
                   });
 
 并在使用过程中，以某种方式在人物对象上使用EvalExpression并获取属性值。 我不知道从哪里开始，或者有什么样的语法可以让这样的属性可以评估。 我很新的功能代表和表达式树，我甚至不知道正确的关键字来搜索。 希望我的描述很明确; 如果没有，请告诉我，我会在必要时提供详情。 任何援助将不胜感激。 

I have a working setup which is not strongly typed and relies on reflection.
 
I have a class, say
 
class Person{

    public string FirstName {get ; set;}
    public string LastName {get; set;}
    public int Age {get; set;}
    ...  
    // some more public properties
}
 
and 
 
class CellInfo {
     public string Title {get; set;}
     public string FormatString {get; set;}
}
 
and I have a dictionary like this
 
Dictionary<string, CellInfo> fields = new Dictionary<string, CellInfo>();
fields.Add("FirstName", new CellInfo {Title = "First Name", FormatString = "Foo"});
fields.Add("LastName", new CellInfo {Title = "Last Name", FormatString = "Bar"});
 
It's a simple dictionary with property Names and some info about them. I pass the dictionary to another module that processes Person instances and I do
 
Dictionary<string, CellInfo> fields = SomeMethodToGetDictionary();
foreach(Person p in someCollection)
{
    foreach(var field in fields)
    { 
       object cellValue = type(Person).GetProperty(field.Key).GetValue(p, null);
       // use cellValue and info on field from field.Value somewhere.
       ...
    }
 }
 
This method of passing the string for field name and using reflection works, but I was wondering if there is a strongly-typed method of doing this.
 
What I had in mind was having a property that stored a linq expression, something like this 
 
fields.Add("FirstName", new CellInfo 
                   {
                      Title = "First Name", 
                      FormatString = "Foo",
                      EvalExpression = p => p.FirstName
                   });
 
and during usage, somehow use the EvalExpression on a person object and get the property value. I have no clue where to begin or what the syntax would be like to have a property like this that's evaluateable. I'm new to function delegates and expression trees that I don't even know the right keywords to search for. Hope my description is clear; if not, let me know and I'll details as necessary. Any assistance would much appreciated.

原文：https://stackoverflow.com/questions/7527536