在Reflection中，PropertyInfo和FieldInfo有什么区别？

public   class   Test  
  {  
    public   int   A;  
    private   int   _b;  
    public   int   B  
    {  
        get  
        {  
            return   _b;  
        }  
    }  
  }  
   
  A就是Field，B就是Property。那么什么是FieldInfo,什么是PropertyInfo应该很显然了。不过呢，二者的确很相似也应该很相似（A，B不也很相似吗）：都继承自MemberInfo。
 
Public Sub CopyEntity(ByRef DestObj As Object, ByRef SrcObj As Object)
        Dim type As Type = SrcObj.GetType()
        Dim p As PropertyInfo() = type.GetProperties()
        Dim i As Integer
        For i = 0 To p.Length - 1
            p(i).SetValue(DestObj, p(i).GetValue(SrcObj, Nothing), Nothing)
        Next
    End Sub

 Private Function GetCriteria(ByVal fieldName As String) As AddrBookCriteria
        Dim criteria As AddrBookCriteria = New AddrBookCriteria()
        criteria.COMPCODE = Me.txtCode.Text.Trim
        Dim type As Type = criteria.GetType()
        Dim field As System.Reflection.FieldInfo = type.GetField(fieldName)
        If field Is Nothing Then
            Throw New Exception(String.Format("There is not this type[{0}] in the AddrBook", fieldName))
        End If
        field.SetValue(criteria, True)
        Return criteria
    End Function