Difference between datacontract and messagecontract in wcf

在WCF中有两种契约各自是DataContract和MessageContract，这篇博客来讲一下两者的差别。先看一下两者定义契约实体的方式有和不同。

1.数据契约

<span style="font-family:SimSun;font-size:18px;"><span style="font-family:SimSun;font-size:18px;">using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Runtime.Serialization;
namespace EmployeeService
{

   [DataContract(Namespace="http://Employee/employee")]

    public class Employee
    {
        private int _id;
        private string _name;
        private string _gender;
        private DateTime _dateOfBirth;

        [DataMember(Name="id",Order=1)]
        public int ID
        {
            get { return _id; }
            set { _id = value; }
        }

        [DataMember(Name = "Name", Order = 2)]
        public string Name
        {
            get { return _name; }
            set { _name = value; }
        }

        [DataMember(Name = "Gender", Order = 2)]
        public string Gender
        {
            get { return _gender; }
            set { _gender = value; }
        }

        public DateTime DateOfBirth
        {
            set { _dateOfBirth = value; }
            get { return _dateOfBirth; }
        }

    }
}
</span></span>

2.消息契约

<span style="font-family:SimSun;font-size:18px;"><span style="font-family:SimSun;font-size:18px;">using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Runtime.Serialization;
using System.ServiceModel;
namespace EmployeeService
{

   [MessageContract(IsWrapped=true,WrapperName="EmployeeInfoObject",WrapperNamespace="http://Employee")]
    public class Employee
    {
        private int _id;
        private string _name;
        private string _gender;
        private DateTime _dateOfBirth;

       [MessageBodyMember(Order=1,Namespace="http://Employee")]
        public int ID
        {
            get { return _id; }
            set { _id = value; }
        }

       [MessageBodyMember(Order = 2, Namespace = "http://Employee")]
        public string Name
        {
            get { return _name; }
            set { _name = value; }
        }

      [MessageBodyMember(Order = 3, Namespace = "http://Employee")]
        public string Gender
        {
            get { return _gender; }
            set { _gender = value; }
        }

       [MessageBodyMember(Order = 4, Namespace = "http://Employee")]
        public DateTime DateOfBirth
        {
            set { _dateOfBirth = value; }
            get { return _dateOfBirth; }
        }

    }
}
</span></span>

3.差别一：DataContract gives very limited control over the SOAP message.

我们在先前的博客中也提到过，通过採用数据契约的方式能够改变XML元素在主体部分中的位置。仅仅有这些，因此数据契约并没有太多的控制对SOAP协议。

4. MessagecContract gives full control.

与数据契约比較的话。消息契约能够做到全然的控制SOAP协议，比方生成的XML元素header和body部分。因此採用消息契约的话，能够全然控制SOAP协议。因此也能够对我们一些敏感的信息做一下保护。

具体请參考：消息契约（Message Contract）和基于消息契约的序列化