WebService – 2.动态调用WebService

在本节课程中，将演示如何通过程序动态添加、调用、编译、执行WebService并返回结果。

WebService动态调用示意图

WebService相关知识
代码文档对象模型CodeDom的使用
编程使用C#编译器
反射

1.先建动态调用辅助类 WebServiceHelper.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
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;


namespace InvokeWebService
{
    public static class WebServiceHelper
    {
        /// <summary>
        /// 动态调用WebService
        /// </summary>
        /// <param name="Url">WebService地址</param>
        /// <param name="methodname">WebService方法名（模块名）</param>
        /// <param name="args">调用接口的参数列表</param>
        /// <returns></returns>
        public static object InvokeWebService(string Url,string methodname,object[] args)
        {
            return InvokeWebService(Url, null, methodname, args);
        }

        /// <summary>
        /// 动态调用WebService
        /// </summary>
        /// <param name="Url">WebService地址</param>
        /// <param name="className">类名</param>
        /// <param name="methodname">WebService方法名</param>
        /// <param name="args">调用接口的参数列表</param>
        /// <returns></returns>
        public static object InvokeWebService(string Url, string className, string methodname, object[] args)
        {
            string @namespace = "ServiceBase.WebSerice.DynamicWebLoad";
            if (className == null || className == "")
            {
                className = WebServiceHelper.GetClassName(Url);
            }
            //1.服务描述语言（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);

            //2.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();
            //3.设定编译器的参数
            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");
            //4.变异代理类
            CompilerResults cr = icc.CompileAssemblyFromDom(cplist, ccu);
            if (true==cr.Errors.HasErrors)
            {
                System.Text.StringBuilder sb = new StringBuilder();
                foreach (CompilerError ce in cr.Errors)
                {
                    sb.Append(ce.ToString());
                    sb.Append(System.Environment.NewLine);
                }
                throw new Exception(sb.ToString());
            }
            //生成代理实例，并调用方法
            System.Reflection.Assembly assembly = cr.CompiledAssembly;
            Type t = assembly.GetType(@namespace + "." + className, true, true);
            object obj = Activator.CreateInstance(t);
            System.Reflection.MethodInfo mi = t.GetMethod(methodname);
            return mi.Invoke(obj, args);
        }

        //获取类名
        private static string GetClassName(string url)
        {
            string[] parts = url.Split('/');
            string[] pps = parts[parts.Length - 1].Split('.');
            return pps[0];
        }
    }
}

2.建WebService，  Service1.asmx

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;

namespace InvokeServices
{
    /// <summary>
    /// Service1 的摘要说明
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    [System.ComponentModel.ToolboxItem(false)]
    // 若要允许使用 ASP.NET AJAX 从脚本中调用此 Web 服务，请取消注释以下行。
    // [System.Web.Script.Services.ScriptService]
    public class Service1 : System.Web.Services.WebService
    {

        [WebMethod]
        public string HelloWorld(string Temp1,string Temp2)
        {
            return string.Format("参数1：{0},参数2：{1}", Temp1, Temp2);
        }
    }
}

3.建应用程序

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace Test
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string url = "http://localhost:4547/Service1.asmx";
            string[] args = new string[2];
            args[0] = this.textBox1.Text;
            args[1] = this.textBox2.Text;
            object result = InvokeWebService.WebServiceHelper.InvokeWebService(url, "HelloWorld", args);

            this.textBox3.Text = result.ToString();
        }
    }
}