调用WebService第三方ImportData方法时遇InvalidOperationException错误求助

我需要通过SOAP XML格式向第三方应用发送数据，已添加其WSDL引用，目标ImportData方法可用，该方法包含一个CDATA类型的参数。在SOAPUI中测试请求和响应一切正常，数据能成功插入第三方应用；但在WCF中构造CDATA并调用ImportData方法时，抛出InvalidOperationException错误。

错误信息 #

InvalidOperationException: The top XML element 'Response' from namespace '' references distinct types System.String and System.Object. Use XML attributes to specify another XML name or namespace for the element or types.

SOAPUI请求示例 #

<soapenv:Envelope xmlns:soapenv=http://schemas.xmlsoap.org/soap/envelope/ xmlns:sec=http://schemas.xmlsoap.org/ws/2003/06/secext xmlns:wsu=http://schemas.xmlsoap.org/ws/2003/06/utility xmlns:urn="urn:ThirdParty">
   <soapenv:Header>
      <sec:Security>
         <sec:UsernameToken wsu:Id="ThirdParty">
            <sec:Username>abcd</sec:Username>
            <!--Optional:-->
            <sec:Password>abcd</sec:Password>
         </sec:UsernameToken>
      </sec:Security>
   </soapenv:Header>
   <soapenv:Body>
     <urn:ImportData>
         <Table>Persons</Table>
         <FolderId>0</FolderId>
         <Data><![CDATA[<Document>
         <Record>
    <FirstName>Test USer</FirstName>
    <LastName>Test USer</LastName>
    <IsMainRole>Yes</IsMainRole>
    <IsHomeSite>Yes</IsHomeSite>
    <AccountStatus>System Administrator</AccountStatus>
    <IsClient/>
    <UserId>test_user</UserId>
    <Email>testuser@testuser.com</Email>
    <UserName>test_user</UserName>
    <HOFirstAxis>None</HOFirstAxis>
    <ModulesIMS>2</ModulesIMS>
    <InspectionType/>
    <RoleName>Main</RoleName>
    <Extra>mmeyers</Extra>
    <FunctionalGroups/>
    <SelectAllCalendarsByDefault>Yes</SelectAllCalendarsByDefault>
    <GroupNameho>&lt;None&gt;</GroupNameho>
    <GroupNameTCK>&lt;None&gt;</GroupNameTCK>
    <GroupNameIMS>&lt;None&gt;</GroupNameIMS>
    <GroupNameacs>&lt;None&gt;</GroupNameacs>
    <GroupNameAP>&lt;None&gt;</GroupNameAP>
    <GroupNameMoC>&lt;None&gt;</GroupNameMoC>
    <GroupNameRCM>&lt;None&gt;</GroupNameRCM>
    <DisplayUserLang>English</DisplayUserLang>
    <UseUserRS>No</UseUserRS>
    <TimeZone/>
  </Record>
         </Document>]]></Data>
         <FormatType>3</FormatType>
         <CSVSeparator>1</CSVSeparator>
         <FormatOptions>22</FormatOptions>
         <ImportType>2</ImportType>
         <MatchType>1</MatchType>
         <ImportOptions>1234</ImportOptions>
      </urn:ImportData>
   </soapenv:Body>
</soapenv:Envelope>

WCF代码示例 #

[WebMethod]
[SoapHeader("header", Direction = SoapHeaderDirection.InOut)]
public string CreateXmlForImport()
{
 
    ThirdPartyClient client = new ThirdPartyClient();

        const string FILENAME = @"test.xml";
        XDocument doc = XDocument.Load(FILENAME);
        XNamespace nsUrn = doc.Root.GetNamespaceOfPrefix("urn");
        XElement importData = doc.Descendants(nsUrn + "ImportData").FirstOrDefault();
    XElement xCdata = new XElement("Document",
                            new XElement("Record",
                             new XElement("UserName", "T12345"),
                               new XElement("FirstName", "TEST_RP"),
                               new XElement("LastName", "Test_LNAME"),
                               new XElement("Email", "test@test.com")
                           ));

        string cDataStr = xCdata.ToString();
        XCData cdata = new XCData(cDataStr);

    
   var response = client.ImportData(cDataStr);
    
    return response;
}

解决方案 #

问题根源 #

1. WCF客户端代理生成时，错误解析了ImportData的返回值或参数类型，导致XML序列化出现类型冲突。
2. 代码直接传入字符串cDataStr，WCF默认会对字符串做XML转义，而非包裹成CDATA节点，引发服务端解析异常，返回不符合预期的响应，进而触发序列化错误。
3. WCF调用时未传入SOAPUI请求中的完整参数（如Table、FolderId等），服务端返回异常响应，导致序列化失败。

修复步骤 #

1. 正确构造CDATA并指定序列化方式
   避免直接传入字符串，通过XmlCDataSection构造CDATA节点，并使用自定义数据契约确保WCF将参数序列化为CDATA格式：

   // 匹配接口定义的请求数据契约
   [DataContract(Name = "ImportData", Namespace = "urn:ThirdParty")]
   public class ImportDataRequest
   {
       [DataMember(Name = "Table")]
       public string Table { get; set; }
   
       [DataMember(Name = "FolderId")]
       public int FolderId { get; set; }
   
       [DataMember(Name = "Data")]
       public XmlNode Data { get; set; }
   
       [DataMember(Name = "FormatType")]
       public int FormatType { get; set; }
   
       // 按需添加其他参数
   }
   
   // 重构调用逻辑
   public string CreateXmlForImport()
   {
       ThirdPartyClient client = new ThirdPartyClient();
   
       XElement xCdata = new XElement("Document",
                           new XElement("Record",
                            new XElement("UserName", "T12345"),
                              new XElement("FirstName", "TEST_RP"),
                              new XElement("LastName", "Test_LNAME"),
                              new XElement("Email", "test@test.com")
                          ));
   
       // 构造CDATA节点
       XmlDocument xmlDoc = new XmlDocument();
       XmlCDataSection cdataNode = xmlDoc.CreateCDataSection(xCdata.ToString());
       XmlElement dataElement = xmlDoc.CreateElement("Data");
       dataElement.AppendChild(cdataNode);
   
       ImportDataRequest request = new ImportDataRequest
       {
           Table = "Persons",
           FolderId = 0,
           Data = dataElement,
           FormatType = 3,
           // 填充剩余必填参数
       };
   
       var response = client.ImportData(request);
       return response;
   }
   

2. 修正WCF客户端代理类型
   重新生成客户端代理（使用svcutil.exe或添加服务引用时勾选"始终生成消息契约"），确保参数和返回值类型与WSDL定义一致。若返回值的Response元素存在类型冲突，手动调整数据契约属性：

   [XmlRoot(Namespace = "urn:ThirdParty", ElementName = "Response")]
   public class ImportDataResponse
   {
       [XmlElement(ElementName = "Result")]
       public string Result { get; set; }
   }
   

3. 传入完整参数
   确保调用ImportData时传入SOAPUI请求中的所有必填参数（如CSVSeparator、ImportType等），避免服务端返回异常响应。

内容的提问来源于stack exchange，提问作者RKh