动态调用web服务
我网上找了个动态动用的例子
using System;
using System.IO;
using System.Configuration;
using System.CodeDom;
using System.CodeDom.Compiler;
using System.Net;
using System.Web.Services;
using System.Web.Services.Description;
using Microsoft.CSharp;
using System.Collections;
using System.Reflection;
namespace WuYou.NetSignUp
{
/// <summary>
/// WebServiceHelper 的摘要说明。
/// </summary>
public class WebServiceHelper
{
private string @namespace = "EnterpriseServerBase.WebService.DynamicWebCalling" ; //命名空间
private Assembly assembly = null; //程序集;
private string classname = string.Empty; //类名称;
private Type t; //表示类型;
private object obj = null; //表示实例;
private Boolean isSuccess = false; //是否创建实例成功;
public WebServiceHelper(string Url,string classname)
{
if(classname == null || classname == string.Empty)
this.classname = GetWsClassName(Url);
else
this.classname = classname;
try
{
//获取WSDL
WebClient wc = new WebClient();
Stream stream = wc.OpenRead(Url+"?WSDL");
ServiceDescription sd = ServiceDescription.Read(stream);
ServiceDescriptionImporter sdi = new ServiceDescriptionImporter();
sdi.AddServiceDescription(sd,"","");
CodeNamespace cn = new CodeNamespace(@namespace);
stream.Close();
//生成客户端代理类代码
CodeCompileUnit ccu = new CodeCompileUnit();
ccu.Namespaces.Add(cn);
sdi.Import(cn ,ccu);
CSharpCodeProvider csc = new CSharpCodeProvider();
ICodeCompiler icc = csc.CreateCompiler();
//设定编译参数
CompilerParameters cplist = new CompilerParameters();
cplist.GenerateExecutable = false;
cplist.GenerateInMemory = true;
cplist.ReferencedAssemblies.Add("System.dll");
cplist.ReferencedAssemblies.Add("System.XML.dll");
cplist.ReferencedAssemblies.Add("System.Web.Services.dll");
cplist.ReferencedAssemblies.Add("System.Data.dll");
//编译代理类
CompilerResults cr = icc.CompileAssemblyFromDom(cplist, ccu);
if(true == cr.Errors.HasErrors)
{
System.Text.StringBuilder sb = new System.Text.StringBuilder();
foreach(System.CodeDom.Compiler.CompilerError ce in cr.Errors)
{
sb.Append(ce.ToString());
sb.Append(System.Environment.NewLine);
}
throw new Exception(sb.ToString());
}
assembly = cr.CompiledAssembly;
}
catch (System.Exception ex)
{
throw new Exception(ex.InnerException.Message,new Exception(ex.InnerException.StackTrace));
}
}
private Boolean CreateInstance()
{
try
{
t = assembly.GetType(@namespace+"."+classname,true,true);
obj = Activator.CreateInstance(t);
isSuccess = true;
}
catch (System.Exception e)
{
throw new Exception(e.Message);
}
return isSuccess;
}
public object InvokeWebService(string methodanme,object[] parms)
{
if(!isSuccess)
{
CreateInstance();
}
try
{
System.Reflection.MethodInfo mi = t.GetMethod(methodanme);
return mi.Invoke(obj,parms);
}
catch (System.Exception ex)
{
throw new Exception(ex.InnerException.Message,new Exception(ex.InnerException.StackTrace));
}
}
private string GetWsClassName(string wsUrl)
{
string[] parts = wsUrl.Split('/') ;
string[] pps = parts[parts.Length-1].Split('.') ;
return pps[0] ;
}
}
}
然后调用本地的
string url = "http://localhost/DymaticText/Service1.asmx" ;
string[] args=new string[2];
args[0] ="strere";
args[1] = "China" ;
object result = Proxy.InvokeWebService(url ,"HelloWorld " ,args) ;
this.label3.Text = result.ToString() ;
就出现错误"未将对象引用设置到对象的实例"
用网上别人提供的例子就可以测试成功
这是为什么?
谁碰到过这个问题并且解决了的告诉我一下啊