C#动态调用webService问题。。。如何调用web Service的返回值是Double型和Float型的

Question

在Winform窗体下调用这个WebServiceHelper.cs类，要求Web Service里的返回值只能是String型的或者DataSet型，要如何修改才能调用返回值是Double型和float型。。***************************************************************
类WebServiceHelper.cs
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using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.IO;
using System.CodeDom;
using Microsoft.CSharp;
using System.CodeDom.Compiler;
using System.Web.Services.Description;
using System.Web.Services.Protocols;namespace WebSs
{
    public class WebServiceHelper
    {
        
      
        public static object InvokeWebService(string url, string methodname, object[] args)
        {
            try
            {
                // 定义
                string @namespace = "WebService.DynamicWebCalling";
                string[] parts = url.Split('/');
                string[] pps = parts[parts.Length - 1].Split('.');
                string classname = pps[0];                //获取URL
                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);                //生成客户端代理类
                CodeCompileUnit ccu = new CodeCompileUnit();
                ccu.Namespaces.Add(cn);
                sdi.Import(cn, ccu);
                CSharpCodeProvider icc = new CSharpCodeProvider();
                //Microsoft.CSharp.CSharpCodeProvider csc = new Microsoft.CSharp.CSharpCodeProvider();
                //System.CodeDom.Compiler.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");                
                CompilerResults cr = icc.CompileAssemblyFromDom(cplist, ccu);
                if (true == cr.Errors.HasErrors)
                {
                    StringBuilder sb = new StringBuilder();
                    foreach (System.CodeDom.Compiler.CompilerError ce in cr.Errors)
                    {
                        sb.Append(ce.ToString());
                        sb.Append(System.Environment.NewLine);
                    }
                    throw new Exception(sb.ToString());
                }                
                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);
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
    }
}
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winForm窗体，调用代码
***************************************************************
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;namespace WebSs
{
    public partial class DynamicWeb : Form
    {
        public DynamicWeb()
        {
            InitializeComponent();
            cmbAddress.Items.Add("http://localhost/WebService/Service.asmx");
            cmbAddress.Items.Add("http://localhost/WebService/Welcome.asmx");
            cmbAddress.Items.Add("http://localhost/WebService/GoodsInfo.asmx");
        }        private void btnCall_Click(object sender, EventArgs e)
        {
            try
            {
                string wsAddress = cmbAddress.Text.Trim();
                string wsMethod = txtMethod.Text.Trim();
                object[] wsParameter = null;
                if (txtParameter.Text.Trim() != "")
                {
                    wsParameter = txtParameter.Text.Trim().Split(',');
                }
                object result = WebServiceHelper.InvokeWebService(wsAddress, wsMethod, wsParameter);
                if (result == null)
                {
                    txtResult.Text = "null";
                    dgResult.DataSource = null;
                    return;
                }
                if (result.GetType().FullName == "System.Data.DataSet")
                {
                    DataSet ds = (DataSet)result;
                    dgResult.DataSource = ds.Tables[0].DefaultView;
                    txtResult.Text = "";
                }
                else
                {
                    txtResult.Text = result.ToString();
                    dgResult.DataSource = null;
                }            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }        
    }
}
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在Winform窗体下调用这个WebServiceHelper.cs类，要求Web Service里的返回值只能是String型的或者DataSet型，要如何修改才能调用返回值是Double型和float型。。

Answer 1

将WebService的返回类型改为需要的Double型和float就行了。

Answer 2

一调用下面这方法，就显示：类型“System.String”的对象无法转换为类型“System.Double”
[WebMethod]
    public double TriangleSquare(double a, double b, double c)
    {
        double p, square;
        p = (a + b + c) / 2.0;
        square = System.Math.Sqrt(p * (p - a) * (p - b) * (p - c));
        return square;
    }

Answer 3

请确定当你添加web reference，这个方法是最新的，你也可以在web service 类里面对你写的这个方法进行调试。 这个问题不复杂，你自己要仔细，要学会调试程序。