功能:
可以辅助TextBox控件自动输入,如在google中搜索时。
属性:
TargetControlID:指定将被辅助完成自动输入的控件ID,这里的控件只能是TextBox;
ServicePath:指出提供服务的WEB服务路径,若不指出则ServiceMethod表示本页面对应的方法名;
ServiceMethod:指出提供服务的方法名;
MinimumPrefixLength:指出开始提供提示服务时,TextBox控件应有的最小字符数,默认为3;
CompletionSetCount:显示的条数,默认为10;
EnableCaching:是否在客户端缓存数据,默认为true;
CompletionInterval:从服务器读取数据的时间间隔,默认为1000,单位:毫秒。
代码实例:
ASPX页面代码:
<head runat="server">
<title>AutoComplete server control</title>
</head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager runat="server" ID="ScriptManager1" />
<cc1:AutoCompleteExtender
ID="AutoCompleteExtender1"
runat="server"
ServicePath="AutoComplete.asmx"
TargetControlID="TextBox1"
ServiceMethod="GetWordList"
MinimumPrefixLength="1"
EnableCaching ="true"
CompletionSetCount="12"
CompletionInterval="1000">
</cc1:AutoCompleteExtender>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</form>
</body>
</html>
编写相应的webservices
public AutoComplete () {
//Uncomment the following line if using designed components
//InitializeComponent();
}
private static string[] autoCompleteWordList = null;
[WebMethod]
public String[] GetWordList(string prefixText, int count)
{
if (autoCompleteWordList == null)
{
string[] temp = File.ReadAllLines(Server.MapPath("~/App_Data/words.txt"));
Array.Sort(temp, new CaseInsensitiveComparer());
autoCompleteWordList = temp;
}
int index = Array.BinarySearch(autoCompleteWordList, prefixText,
new CaseInsensitiveComparer());
if (index < 0)
{
index = ~index;
}
int matchingCount;
for (matchingCount = 0;
matchingCount < count && index + matchingCount <
autoCompleteWordList.Length;
matchingCount++)
{
if (!autoCompleteWordList[index +
matchingCount].StartsWith(prefixText,
StringComparison.CurrentCultureIgnoreCase))
{
break;
}
}
String[] returnValue = new string[matchingCount];
if (matchingCount > 0)
{
Array.Copy(autoCompleteWordList, index, returnValue, 0,
matchingCount);
}
return returnValue;
}
}
在这里需要注意以下几点:
1.由于该WEB服务是为Ajax框架提供服务的,因此在类声明之前得加上属性声明:
[System.Web.Script.Services.ScriptService]
2.特别需要注意的是GetTextString这个方法。凡是为AutoCompleteExtender控件提供服务的方法都必需完全满足以下三个条件:
A.方法的返回类型必需为:string [];
B.方法的传入参数类型必需为:string , int;
C.两个传入参数名必需为:prefixText , count。
在App_Data下添加words.txt。
ADO.NET
aggregate event
alpha channel
anchoring
antialiasing
application base
application domain (AppDomain)
application manifest
application state
ASP.NET
ASP.NET application services database
ASP.NET mobile controls
ASP.NET mobile Web Forms
ASP.NET page
ASP.NET server control
ASP.NET Web application
运行结果: