WCF分布式开发常见错误解决(7):Cannot have two operations in the same contract

我们启动服务宿主程序的时候，有可能出现如下的无效操作异常，信息如下：
Cannot have two operations in the same contract with the same name, methods SayHello and SayHello in type WCFService.IWCFService violate this rule. You can change the name of one of the operations by changing the method name or by using the Name property of OperationContractAttribute.异常信息截图：



原因：这个是由于服务契约里定义了定义了两个相同名称的操作契约。
解决办法：
1.重新定义操作契约的名称，使两者不同；
2.或者使用操作契约的名称属性，实例代码如下：
//1.服务契约,操作契约重载
[ServiceContract(Namespace = "http://www.cnblogs.com/frank_xl/")]
public interface IWCFService
{
//操作契约
[OperationContract(Name = "SayHello1")]
string SayHello();
//操作契约
[OperationContract(Name = "SayHello2")]
string SayHello(string name);
//操作契约
[OperationContract(Name = "SayHello3")]
string SayHello(string firstName, string lastName);

}

重新编译运行代码即可。