مشکل در صدا زدن متد وب سرویس

[mahtab kf]

سلام
من متد زیر را برای صدا زدن متد استفاده کردم اما wsvcClass مقدار null میگیره و در نتیجه error میده
ممنون میشم دلیلشو برام بگید


[SecurityPermissionAttribute(SecurityAction.Demand, Unrestricted = true)]
public object CallWebService(string serviceName, string methodName, object[] args)
{
System.Net.WebClient client = new System.Net.WebClient();

//// Connect To the web service
System.IO.Stream stream = client.OpenRead("مسیر وب سرویس");

//// Now read the WSDL file describing a service.
ServiceDescription description = ServiceDescription.Read(stream);

ServiceDescriptionImporter importer = new ServiceDescriptionImporter();
importer.ProtocolName = "Soap12"; // Use SOAP 1.2.
importer.AddServiceDescription(serviceDescription, null, null);

// Generate a proxy client.
importer.Style = ServiceDescriptionImportStyle.Client;

// Generate properties to represent primitive values.
importer.CodeGenerationOptions = System.Xml.Serialization.CodeGenerationOptions.Gen erateProperties;

// Initialize a Code-DOM tree into which we will import the service.
CodeNamespace nmspace = new CodeNamespace();
CodeCompileUnit unit1 = new CodeCompileUnit();
unit1.Namespaces.Add(nmspace);

// Import the service into the Code-DOM tree. This creates proxy code that uses the service.
ServiceDescriptionImportWarnings warning = importer.Import(nmspace, unit1);

if (warning == 0)
{
// Generate the proxy code
CodeDomProvider provider1 = CodeDomProvider.CreateProvider("CSharp");

// Compile the assembly proxy with the appropriate references
string[] assemblyReferences = new string[5] { "System.dll", "System.Web.Services.dll", "System.Web.dll", "System.Xml.dll", "System.Data.dll" };

CompilerParameters parms = new CompilerParameters(assemblyReferences);

CompilerResults results = provider1.CompileAssemblyFromDom(parms, unit1);

// Check For Errors
if (results.Errors.Count > 0)
{
foreach (CompilerError oops in results.Errors)
{
System.Diagnostics.Debug.WriteLine("========Compiler error============");
System.Diagnostics.Debug.WriteLine(oops.ErrorText) ;
}
throw new System.Exception("Compile Error Occured calling webservice. Check Debug ouput window.");
}

// Finally, Invoke the web service method

object wsvcClass = results.CompiledAssembly.CreateInstance(serviceNam e);

MethodInfo mi = wsvcClass.GetType().GetMethod(methodName);

return mi.Invoke(wsvcClass, args);

}

else
{
return null;
}
}

[mahtab kf]

کسی نمیتونه منو راهنمایی کنه؟