类似百度Google的搜索

界面：Code
//WebService的写法
using System;
using System.Web;
using System.Collections;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Data;
using System.Data.SqlClient;
/// <summary>
/// WebService 的摘要说明
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]

[System.Web.Script.Services.ScriptService]
public class WebService : System.Web.Services.WebService {

public WebService () {

//如果使用设计的组件，请取消注释以下行
//InitializeComponent();
}

[WebMethod]
public string[] GetData(string prefixText,int count)
{
SqlConnection conn = new SqlConnection("server=.;database=Northwind;uid=sa;pwd=;");
string Str = "select CompanyName from Customers where CompanyName like '" + prefixText + "%' order by CompanyName ";
SqlDataAdapter sda = new SqlDataAdapter(Str,conn);
DataSet ds=new DataSet();
sda.Fill(ds,"com");

string[] temp=new string[ds.Tables["com"].Rows.Count];
for(int i=0;i<ds.Tables["com"].Rows.Count;i++)
{
temp[i] = ds.Tables["com"].Rows[i]["CompanyName"].ToString();
}

return temp;
}

}

需要在界面中设定AutoCompleteExtender的属性如图：




设置TargetControlID 为你要控制的控件这里我设置的是TextBox1

这个时候TextBox1就多了个属性





设置ServiceMethod属性为你的WebService 中的方法

设置ServicePath为你的WebService文件的名称