.net 调用 WCF 服务操作时出现 HTTP 400 错误请求？
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HTTP 400 Bad Request when calling WCF Service Operation?
提问by Xaisoft
When I call http://localhost/TestService.svc/GetColors, I get a Http (400) Bad Request. When I run this in fiddler, I also get Bad Request. When I invoke the service through the wcf test client, it works fine though. What could cause this?
当我调用http://localhost/TestService.svc/GetColors 时，我收到一个 Http (400) 错误请求。当我在 fiddler 中运行它时，我也会收到错误的请求。当我通过 wcf 测试客户端调用服务时，它工作正常。什么可能导致这种情况？
Service contract:
服务合约：
[ServiceContract]
public interface ITestService
{
[OperationContract]
string GetColors();
}
Implementation of ITestService:
ITestService 的实现：
[ServiceBehavior(InstanceContextMode=InstanceContextMode.Single)]
public class TestService : ITestService
{
public List<Color> GetColors()
{
List<Color> colors= new List<Color>();
colors.Add(new Color { Name = "Red", Code = "123" });
colors.Add(new Color { Name = "Blue", Code = "323" });
colors.Add(new Color { Name = "Green", Code = "3394" });
return colors;
}
}
Here is my web.config:
这是我的 web.config：
<?xml version="1.0"?>
<configuration>
<system.web>
<compilation debug="true" targetFramework="4.0"/>
</system.web>
<system.serviceModel>
<bindings>
<wsHttpBinding>
<binding name="CustomAuthentication">
<security mode="Message">
<message clientCredentialType="UserName"/>
</security>
</binding>
</wsHttpBinding>
</bindings>
<serviceHostingEnvironment multipleSiteBindingsEnabled="true"/>
<services>
<service name="TestService.TestService"
behaviorConfiguration="CustomValidator" >
<endpoint
address=""
binding="wsHttpBinding"
bindingConfiguration="CustomAuthentication"
contract="TestService.ITestService">
<identity>
<dns value="localhost" />
</identity>
</endpoint>
<endpoint
address="mex"
binding="mexHttpBinding"
contract="IMetadataExchange" />
<host>
<baseAddresses>
<add baseAddress="http://localhost/TestService/" />
</baseAddresses>
</host>
</service>
</services>
<behaviors>
<serviceBehaviors>
<behavior name="CustomValidator">
<serviceCredentials>
<userNameAuthentication userNamePasswordValidationMode="Custom"
customUserNamePasswordValidatorType="TestService.CustomUserNameValidator, TestService"/>
<serviceCertificate findValue="Test" storeLocation="LocalMachine"
storeName="My" x509FindType="FindBySubjectName"/>
</serviceCredentials>
<serviceMetadata httpGetEnabled="True"/>
</behavior>
<behavior>
<serviceMetadata httpGetEnabled="True"/>
<serviceDebug includeExceptionDetailInFaults="False"/>
</behavior>
</serviceBehaviors>
</behaviors>
</system.serviceModel>
<system.webServer>
<modules runAllManagedModulesForAllRequests="true"/>
</system.webServer>
</configuration>
When I call it, I just open up a any browser and put the url http://localhost/TestService.svc/GetColors. If I do it through the dev environment, I see the Http 400 bad request. If I do it through IIS, I just see a blank page.
当我调用它时，我只需打开任何浏览器并输入 url http://localhost/TestService.svc/GetColors。如果我通过开发环境执行此操作，则会看到 Http 400 错误请求。如果我通过 IIS 执行此操作，我只会看到一个空白页面。
Here is the InnerException:
这是内部异常：
<ExceptionString>System.Xml.XmlException: The body of the message cannot be read
because it is empty.</ExceptionString>
Another question regarding my CustomUserNameValidation:
关于我的 CustomUserNameValidation 的另一个问题：
I am implementing Custom Validation through the Validate Method of UserNamePasswordValidator, but when I call something like GetColors through the wcf client, it does not invoke the Validate method. The only way I can get it to Invoke validate is if I call Validate(user,pass) directly in GetColors. I thought it woulld be called automatically for every service call if you have it setup correctly in web.config.
我正在通过 UserNamePasswordValidator 的 Validate 方法实现自定义验证，但是当我通过 wcf 客户端调用 GetColors 之类的东西时，它不会调用 Validate 方法。我可以让它调用验证的唯一方法是，如果我直接在 GetColors 中调用 Validate(user,pass)。我认为如果您在 web.config 中正确设置了它，它将为每个服务调用自动调用。
采纳答案by marc_s
Your service contract and service implementation don't seem to match....
您的服务合同和服务实施似乎不匹配....
The service contract defines a single stringto be returned from GetColors():
服务合同定义了一个string从 返回的单曲GetColors()：
[ServiceContract]
public interface ITestService
{
[OperationContract]
string GetColors();
}
But the implementation returns a List<Color>instead:
但是实现返回一个List<Color>：
[ServiceBehavior(InstanceContextMode=InstanceContextMode.Single)]
public class TestService : ITestService
{
public List<Color> GetColors()
{
Is there any chance you changed your service implementation, and forgot to update the service contract??
有没有可能你改变了你的服务实现，忘记更新服务合同？
Also: since this is a SOAP service with a wsHttpBinding, you cannotjust call the method from a browser by browsing to its address - you need to use the WCF Test Client (which works, as you say). Nor can you just call it from Fiddler, either - you would have to manually create the entire SOAP envelope with header and body and all - not an easy task at all.
另外：由于这是一个带有 的 SOAP 服务wsHttpBinding，您不能仅通过浏览到其地址来从浏览器调用该方法 - 您需要使用 WCF 测试客户端（如您所说，它可以工作）。您也不能仅仅从 Fiddler 调用它——您必须手动创建整个 SOAP 信封，包括标题和正文以及所有内容——这根本不是一件容易的事。
What you can try is to go to http://localhost/TestService.svc?wsdlto check whether you'll get back the proper WSDL for the service.
您可以尝试去http://localhost/TestService.svc?wsdl检查您是否会为该服务取回正确的 WSDL。
回答by Simon Mourier
Many things could cause this. I suggest you first enable WCF Tracing, it's usually very helpful as it gives you the server side output of what's really going on. Here is a link that should help: How to enable WCF tracing
很多事情都可能导致这种情况。我建议您首先启用 WCF 跟踪，它通常非常有用，因为它可以为您提供真实情况的服务器端输出。这是一个应该有帮助的链接：如何启用 WCF 跟踪
EDIT: One little thing to note with WCF: unlike auto generated ole' ASMX web service it does not allow you to browseto the base address with a standard browser. You can browse to the Metadata address (the mex one), but not to the root. This is just by design (the HTTP method is not supported I believe).
编辑：一个小一点要注意与WCF：不同于自动生成的OLE” ASMX Web服务不会允许你浏览到的基地址与一个标准的浏览器。您可以浏览到元数据地址（mex 地址），但不能浏览到根。这只是设计使然（我相信不支持 HTTP 方法）。
