.net 当实际服务返回数据时，为什么WebService会返回null？

我有一个网络服务（我无法控制），我必须与之交谈。我还有一个数据包嗅探器，Web服务的开发人员没有撒谎。我在正确的字段中看到数据

他们实际上正在发回我要求的所有数据。但是从WSDL文件自动生成的web服务代码将“null”作为一个值

更新：为了澄清，返回的对象不为空。对象中的元素为空。我不知道这是否对任何人有帮助。我完全被难住了

我使用他们的WSDL文件来生成我的Web引用。我用WSDL文件声明的数据类型检查了我的数据类型。我使用下面列出的代码来执行调用：

DT_MaterialMaster_LookupRequest req = new DT_MaterialMaster_LookupRequest();
req.MaterialNumber = "101*";
req.DocumentNo = "";
req.Description = "Pipe*";
req.Plant = "0000";

MI_MaterialMaster_Lookup_OBService srv = new MI_MaterialMaster_Lookup_OBService();

DT_MaterialMaster_Response resp = 
    srv.MI_MaterialMaster_Lookup_OB(new DT_MaterialMaster_LookupRequest[] { req });


// Note that the response here is ALWAYS null!!
Console.WriteLine(resp.Status);

resp对象是实际对象。它是正确生成的。但是，Status和MaterialData字段始终为空

当我调用web服务时，我在线路上放置了一个数据包嗅探器，我可以看到我已经发送了以下内容（为了我自己的理智，换行符和缩进）：

101*
烟斗*
0000

他们返回的响应似乎是有效的响应（为了我自己的理智，换行符和缩进）：

找不到行

状态显示它实际收到了数据。。。但是resp.Status和resp.MaterialData字段始终为空。我做错了什么

更新： WSDL文件定义为：

<?xml version="1.0" encoding="utf-8"?>
<wsdl:definitions xmlns:p1="http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch" name="MI_MaterialMaster_Lookup_OB" targetNamespace="http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/">
  <wsdl:types>
    <xsd:schema xmlns="http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch" 
        targetNamespace="http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch" 
        xmlns:xsd="http://www.w3.org/2001/XMLSchema">
      <xsd:element name="MT_MaterialMaster_Response" type="p1:DT_MaterialMaster_Response" />
      <xsd:element name="MT_MaterialMaster_Lookup" type="p1:DT_MaterialMaster_Lookup" />
      <xsd:complexType name="DT_MaterialMaster_Response">
    <xsd:sequence>
      <xsd:element name="Status" type="xsd:string">
        <xsd:annotation>
          <xsd:appinfo source="http://SomeCompany.com/xi/TextID">d48d03b040af11df99e300145eccb24e</xsd:appinfo>
        </xsd:annotation>
      </xsd:element>
      <xsd:element maxOccurs="unbounded" name="MaterialData">
        <xsd:annotation>
          <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa040a511df843700145eccb24e</xsd:appinfo>
        </xsd:annotation>
        <xsd:complexType>
          <xsd:sequence>
        <xsd:element name="MaterialNumber" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa140a511df848500145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Description" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa240a511df95bf00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="DocumentNo" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa340a511dfb23700145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="UOM" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">3b5f14c040a611df9fbe00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Hierarchy" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa440a511dfc65b00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Plant" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">d48d03b140af11dfb78e00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Procurement" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">d48d03b240af11dfb87b00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
          </xsd:sequence>
        </xsd:complexType>
      </xsd:element>
    </xsd:sequence>
      </xsd:complexType>
      <xsd:complexType name="DT_MaterialMaster_Lookup">
    <xsd:sequence>
      <xsd:element maxOccurs="unbounded" name="Request">
        <xsd:annotation>
          <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa040a511df843700145eccb24e</xsd:appinfo>
        </xsd:annotation>
        <xsd:complexType>
          <xsd:sequence>
        <xsd:element minOccurs="0" name="MaterialNumber" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa140a511df848500145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Description" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa240a511df95bf00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="DocumentNo" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa340a511dfb23700145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Plant" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa440a511dfc65b00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
          </xsd:sequence>
        </xsd:complexType>
      </xsd:element>
    </xsd:sequence>
      </xsd:complexType>
    </xsd:schema>
  </wsdl:types>
  <wsdl:message name="MT_MaterialMaster_Lookup">
    <wsdl:part name="MT_MaterialMaster_Lookup" element="p1:MT_MaterialMaster_Lookup" />
  </wsdl:message>
  <wsdl:message name="MT_MaterialMaster_Response">
    <wsdl:part name="MT_MaterialMaster_Response" element="p1:MT_MaterialMaster_Response" />
  </wsdl:message>
  <wsdl:portType name="MI_MaterialMaster_Lookup_OB">
    <wsdl:operation name="MI_MaterialMaster_Lookup_OB">
      <wsdl:input message="p1:MT_MaterialMaster_Lookup" />
      <wsdl:output message="p1:MT_MaterialMaster_Response" />
    </wsdl:operation>
  </wsdl:portType>
  <wsdl:binding name="MI_MaterialMaster_Lookup_OBBinding" type="p1:MI_MaterialMaster_Lookup_OB">
    <binding transport="http://schemas.xmlsoap.org/soap/http" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
    <wsdl:operation name="MI_MaterialMaster_Lookup_OB">
      <operation soapAction="http://SomeCompany.com/xi/WebService/soap1.1" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
      <wsdl:input>
    <body use="literal" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
      </wsdl:input>
      <wsdl:output>
    <body use="literal" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
      </wsdl:output>
    </wsdl:operation>
  </wsdl:binding>
  <wsdl:service name="MI_MaterialMaster_Lookup_OBService">
    <wsdl:port name="MI_MaterialMaster_Lookup_OBPort" binding="p1:MI_MaterialMaster_Lookup_OBBinding">
      <address location="http://bxdwas.MyCompany.com/XISOAPAdapter/MessageServlet?channel=:SOAP_SND_Material_Lookup" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
    </wsdl:port>
  </wsdl:service>
</wsdl:definitions>

d48d03b040af11df99e300145eccb24e
64908aa040a511df843700145eccb24e
64908aa140a511df848500145eccb24e
64908aa240a511df95bf00145eccb24e
64908AA340A511DFB2370145ECCB24E
3b5f14c040a611df9fbe00145eccb24e
64908aa440a511dfc65b00145eccb24e
d48d03b140af11dfb78e00145eccb24e
d48d03b240af11dfb87b00145eccb24e
64908aa040a511df843700145eccb24e
64908aa140a511df848500145eccb24e
64908aa240a511df95bf00145eccb24e
64908AA340A511DFB2370145ECCB24E
64908aa440a511dfc65b00145eccb24e

您必须为我发布WSDL，但“Web服务返回Null”几乎总是意味着存在关于XML名称空间的争议-该服务在一个名称空间中向您发送数据，而.NET需要另一个名称空间

---

在本例中，请注意，大多数响应都位于默认名称空间中，即使包装器元素位于

http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch

命名空间。

确保您的服务引用是最新的。当服务WSDL更改但引用未更新时，我们就会遇到这种情况。

好主意。。。我不相信你的回答，因为那是一个好机会。然而，我能够伪造一个数据包，我伪造了他们的数据包，并在各地更改了名称空间。这似乎不是问题所在。它没有崩溃，对象本身也不是空的。对象中的项为空。@Jerry：我将在午餐时尝试更详细地了解这一点，但我必须说WSDL没有显示通常表示混合名称空间的符号。同时，如果您可以查看Reference.cs文件，查看元素上放置了哪些名称空间，并与XML进行比较，那将很好。（你会发誓我让他们寄政府机密）。终于得到了，你不知道吗，这是不同的。显然，每个项现在都是项的数组，而不是单个项，因此为什么它是空的。NET无法确定类型，因此将其保留为空。

<SOAP:Envelope xmlns:SOAP='http://schemas.xmlsoap.org/soap/envelope/'>
<SOAP:Header />
    <SOAP:Body>
        <n0:MT_MaterialMaster_Response
           xmlns:n0='http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch'
           xmlns:prx='urn:SomeCompany.com:proxy:BRD:/1SAI/TAS4FE14A2DE960D61219AE:701:2009/02/10'>
        <Response>
            <Status>No Rows Found</Status>
            <MaterialData />
        </Response>
    </n0:MT_MaterialMaster_Response>
</SOAP:Body>
</SOAP:Envelope>

<?xml version="1.0" encoding="utf-8"?>
<wsdl:definitions xmlns:p1="http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch" name="MI_MaterialMaster_Lookup_OB" targetNamespace="http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/">
  <wsdl:types>
    <xsd:schema xmlns="http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch" 
        targetNamespace="http://MyCompany.com/SomeCompany/mm/MaterialMasterSearch" 
        xmlns:xsd="http://www.w3.org/2001/XMLSchema">
      <xsd:element name="MT_MaterialMaster_Response" type="p1:DT_MaterialMaster_Response" />
      <xsd:element name="MT_MaterialMaster_Lookup" type="p1:DT_MaterialMaster_Lookup" />
      <xsd:complexType name="DT_MaterialMaster_Response">
    <xsd:sequence>
      <xsd:element name="Status" type="xsd:string">
        <xsd:annotation>
          <xsd:appinfo source="http://SomeCompany.com/xi/TextID">d48d03b040af11df99e300145eccb24e</xsd:appinfo>
        </xsd:annotation>
      </xsd:element>
      <xsd:element maxOccurs="unbounded" name="MaterialData">
        <xsd:annotation>
          <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa040a511df843700145eccb24e</xsd:appinfo>
        </xsd:annotation>
        <xsd:complexType>
          <xsd:sequence>
        <xsd:element name="MaterialNumber" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa140a511df848500145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Description" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa240a511df95bf00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="DocumentNo" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa340a511dfb23700145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="UOM" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">3b5f14c040a611df9fbe00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Hierarchy" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa440a511dfc65b00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Plant" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">d48d03b140af11dfb78e00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Procurement" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">d48d03b240af11dfb87b00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
          </xsd:sequence>
        </xsd:complexType>
      </xsd:element>
    </xsd:sequence>
      </xsd:complexType>
      <xsd:complexType name="DT_MaterialMaster_Lookup">
    <xsd:sequence>
      <xsd:element maxOccurs="unbounded" name="Request">
        <xsd:annotation>
          <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa040a511df843700145eccb24e</xsd:appinfo>
        </xsd:annotation>
        <xsd:complexType>
          <xsd:sequence>
        <xsd:element minOccurs="0" name="MaterialNumber" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa140a511df848500145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Description" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa240a511df95bf00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="DocumentNo" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa340a511dfb23700145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
        <xsd:element minOccurs="0" name="Plant" type="xsd:string">
          <xsd:annotation>
            <xsd:appinfo source="http://SomeCompany.com/xi/TextID">64908aa440a511dfc65b00145eccb24e</xsd:appinfo>
          </xsd:annotation>
        </xsd:element>
          </xsd:sequence>
        </xsd:complexType>
      </xsd:element>
    </xsd:sequence>
      </xsd:complexType>
    </xsd:schema>
  </wsdl:types>
  <wsdl:message name="MT_MaterialMaster_Lookup">
    <wsdl:part name="MT_MaterialMaster_Lookup" element="p1:MT_MaterialMaster_Lookup" />
  </wsdl:message>
  <wsdl:message name="MT_MaterialMaster_Response">
    <wsdl:part name="MT_MaterialMaster_Response" element="p1:MT_MaterialMaster_Response" />
  </wsdl:message>
  <wsdl:portType name="MI_MaterialMaster_Lookup_OB">
    <wsdl:operation name="MI_MaterialMaster_Lookup_OB">
      <wsdl:input message="p1:MT_MaterialMaster_Lookup" />
      <wsdl:output message="p1:MT_MaterialMaster_Response" />
    </wsdl:operation>
  </wsdl:portType>
  <wsdl:binding name="MI_MaterialMaster_Lookup_OBBinding" type="p1:MI_MaterialMaster_Lookup_OB">
    <binding transport="http://schemas.xmlsoap.org/soap/http" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
    <wsdl:operation name="MI_MaterialMaster_Lookup_OB">
      <operation soapAction="http://SomeCompany.com/xi/WebService/soap1.1" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
      <wsdl:input>
    <body use="literal" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
      </wsdl:input>
      <wsdl:output>
    <body use="literal" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
      </wsdl:output>
    </wsdl:operation>
  </wsdl:binding>
  <wsdl:service name="MI_MaterialMaster_Lookup_OBService">
    <wsdl:port name="MI_MaterialMaster_Lookup_OBPort" binding="p1:MI_MaterialMaster_Lookup_OBBinding">
      <address location="http://bxdwas.MyCompany.com/XISOAPAdapter/MessageServlet?channel=:SOAP_SND_Material_Lookup" xmlns="http://schemas.xmlsoap.org/wsdl/soap/" />
    </wsdl:port>
  </wsdl:service>
</wsdl:definitions>