一、Web Service是一段内含某种特定功能或商业逻辑（例如：股票报价、身份证号码、信用卡检验等），并允许远程对象通过HTTP来启动和调用，如：在A机器上调用B机器上HelloWorld对象的SayHelloWorld方法。
<%@ WebService Language="C#" Class="HelloWorld"%>
using System.Web.Services;
Public class HelloWorld:Inherits WebService{
[WebMethod]public string SayHelloWorld()
{
Return("HelloWorld");
}
}
<Script Language="C#" runat="Server">
public void Page_Load(object sender,EventArgs e)
{
HelloWorld myHelloWorld=new HelloWorld();
string sReturn=myHelloWorld.SayHelloWorld();
Lable1.Text=sReturn;
}
</Script>
三、另外一个例子
<%@ WebService Language="C#" Class="MathService"%>
using System;
using System.Web.Services;
public class MathService
{
[WebMethod]
public int Add(int a,int b)
{
return a + b;
}
[WebMethod]
public int Substract(int a, int b)
{
return a - b;
}
[WebMethod]
public int Multiply(int a , int b)
{
return a * b;
}
[WebMethod]
public int Divide(int a , int b)
{
if (b==0) return -1;
return a / b;
}
}
调用这个web service
<@ Import Namespace="MathServiceSpace">
<script language="C#" runat="server">
int Operand1 = 0;
int Operand2 = 1;
public void Submit_Click(object sender,EventArgs e)
{
try
{
operand1= Int32.Parse(Operand1.Text);
operand2= Int32.Parse(Operand2.Text);
}
catch (Exception)
{
Result.Text="数字初始化错误";
}
MathService Service=new MathService();
switch (((control)sender).ID)
{
case "Add":
Result.Text="计算结果："+Service.Add(operand1,operand2).ToString;
break;
case "Subtract":
Result.Text="计算结果："+Service.Subtract(operand1,operand2).ToString;
break;
case "Multiply":
Result.Text="计算结果："+Service.Multiply(operand1,operand2).ToString;
break;
case "Divide":
Result.Text="计算结果："+Service.Divide(operand1,operand2).ToString;
break;
}
}
</script>
<html>
<body>
<form runat="server">
Operand1：<asp:TextBox id="Operand1" runat="server"/><br>
Operand2；<asp:TextBox id="Operand2" runat="server"/><br>
<input type="button" id="Add" value="Add" OnServerClick="Submit_Click" runat="server"><br>
<input type="button" id="Subtract" value="Subtract" OnServerClick="Submit_Click" runat="server"><br>
<input type="button" id="Multiply" value="Multiply" OnServerClick="Submit_Click" runat="server"><br>
<input type="button" id="Divide" value="Divide" OnServerClick="Submit_Click" runat="server"><br>
<asp:Label id="Result" runat="server"/>
</form>
</body>
</html>
<%@ WebService Language="C#" Class="HelloWorld"%> using System.Web.Services; Public class HelloWorld:Inherits WebService{
Public 
[WebMethod]public string SayHelloWorld() {
Return("HelloWorld"); }}之后直接放在虚拟目录下就可运行，用.asmx?wsdl 可以看到Web Service 的XML文件。
二、上面例子的简单调用
<Script Language="C#" runat="Server">public void Page_Load(object sender,EventArgs e){ HelloWorld myHelloWorld=new HelloWorld(); string sReturn=myHelloWorld.SayHelloWorld(); Lable1.Text=sReturn;}</Script>三、另外一个例子
<%@ WebService Language="C#" Class="MathService"%>using System;using System.Web.Services;public class MathService{ [WebMethod] public int Add(int a,int b) { return a + b; } [WebMethod] public int Substract(int a, int b) { return a - b; } [WebMethod] public int Multiply(int a , int b) { return a * b; } [WebMethod] public int Divide(int a , int b) { if (b==0) return -1; return a / b; }}调用这个web service
<@ Import Namespace="MathServiceSpace"><script language="C#" runat="server"> int Operand1 = 0; int Operand2 = 1; public void Submit_Click(object sender,EventArgs e) { try { operand1= Int32.Parse(Operand1.Text); operand2= Int32.Parse(Operand2.Text); } catch (Exception) { Result.Text="数字初始化错误"; } MathService Service=new MathService(); switch (((control)sender).ID) { case "Add": Result.Text="计算结果："+Service.Add(operand1,operand2).ToString; break; case "Subtract": Result.Text="计算结果："+Service.Subtract(operand1,operand2).ToString; break; case "Multiply": Result.Text="计算结果："+Service.Multiply(operand1,operand2).ToString; break; case "Divide": Result.Text="计算结果："+Service.Divide(operand1,operand2).ToString; break; } }</script><html><body><form runat="server">Operand1：<asp:TextBox id="Operand1" runat="server"/><br>Operand2；<asp:TextBox id="Operand2" runat="server"/><br><input type="button" id="Add" value="Add" OnServerClick="Submit_Click" runat="server"><br><input type="button" id="Subtract" value="Subtract" OnServerClick="Submit_Click" runat="server"><br><input type="button" id="Multiply" value="Multiply" OnServerClick="Submit_Click" runat="server"><br><input type="button" id="Divide" value="Divide" OnServerClick="Submit_Click" runat="server"><br><asp:Label id="Result" runat="server"/></form></body></html>
