Creating a web service
For this add a new webservice to the project by right clicking on root of application in solution explorer and select add new Item than web service,name it
AutoComplete.asmx or whatever you want, in the code behind of the web
service we write methods to get the records from database and a web
method called
GetCompletionList
which takes text entered in textbox as parameter to search database ,
this method gets automatically called when ever user types anything in
the textbox, the code for this web service is like this
Code behind for AutoComplete.asmx
In the code behind i've written a method called
GetRecords which takes string as parameter to fetch records from databse and a webmethod called
GetCompletionList which also takes string prefixText and int count as input parameters,
GetCompletionList method gets called whenever user enters somthing in TextBox
using System;
using System.Collections.Generic;
using System.Web.Services;
using System.Data.SqlClient;
using System.Configuration;
using System.Data;
[WebService]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[System.Web.Script.Services.ScriptService]
public class AutoComplete : WebService
{
public AutoComplete()
{
}
[WebMethod]
public string[] GetCompletionList(string prefixText, int count)
{
if (count == 0)
{
count = 10;
}
DataTable dt = GetRecords(prefixText);
List<string> items = new List<string>(count);
for (int i = 0; i < dt.Rows.Count; i++)
{
string strName = dt.Rows[i][0].ToString();
items.Add(strName);
}
return items.ToArray();
}
public DataTable GetRecords(string strName)
{
string strConn = ConfigurationManager.ConnectionStrings["DatabaseConnectionString"].ConnectionString;
SqlConnection con = new SqlConnection(strConn);
SqlCommand cmd = new SqlCommand();
cmd.Connection = con;
cmd.CommandType = System.Data.CommandType.Text;
cmd.Parameters.AddWithValue("@Name", strName);
cmd.CommandText = "Select Name from Test where Name like '%'+@Name+'%'";
DataSet objDs = new DataSet();
SqlDataAdapter dAdapter = new SqlDataAdapter();
dAdapter.SelectCommand = cmd;
con.Open();
dAdapter.Fill(objDs);
con.Close();
return objDs.Tables[0];
}
}
Html source of aspx page
In the html source for aspx page add a script manager and within scriptmanager tag , add ServiceReference and path to asmx file, in gridview add autocomplete extender for the textbox which we want to autocomplete like this
<asp:ScriptManager ID="ScriptManager1"
runat="server">
<Services>
<asp:ServiceReference Path="AutoComplete.asmx" />
</Services>
</asp:ScriptManager>
and the settings for autocomplete extender
<ajaxToolkit:AutoCompleteExtender
runat="server"
ID="autoComplete1"
TargetControlID="txtName"
ServicePath="AutoComplete.asmx"
ServiceMethod="GetCompletionList"
MinimumPrefixLength="1"
CompletionInterval="10"
EnableCaching="true"
CompletionSetCount="12" />
Complete soource of the page
<body>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server">
<Services>
<asp:ServiceReference Path="AutoComplete.asmx" />
</Services>
</asp:ScriptManager>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataSourceID="SqlDataSource1">
<Columns>
<asp:CommandField ShowEditButton="True" />
<asp:TemplateField HeaderText="ID" SortExpression="ID">
<ItemTemplate>
<asp:Label ID="lblID" runat="server" Text='<%#Eval("ID") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:Label ID="lblID" runat="server" Text='<%#Bind("ID") %>'></asp:Label>
</EditItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Name" SortExpression="Name">
<ItemTemplate>
<asp:Label ID = "lblName" runat="server" Text='<%#Eval("Name") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:TextBox ID="txtName" runat="server" Text='<%#Bind("Name") %>' ></asp:TextBox>
<ajaxToolkit:AutoCompleteExtender
runat="server"
ID="autoComplete1"
TargetControlID="txtName"
ServicePath="AutoComplete.asmx"
ServiceMethod="GetCompletionList"
MinimumPrefixLength="1"
CompletionInterval="10"
EnableCaching="true"
CompletionSetCount="12" />
</EditItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Location" SortExpression="Location">
<ItemTemplate>
<asp:Label ID="lblLocation" runat="server" Text='<%#Eval("Location") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:Label ID="lblLocation" runat="server" Text='<%#Bind("Location") %>'></asp:Label>
</EditItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</ContentTemplate>
</asp:UpdatePanel>
<div>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:DatabaseConnectionString %>"
SelectCommand="SELECT [ID], [Name], [Location] FROM [Test]" UpdateCommand="Update Test set [Name] = @Name where ID = @ID">
<UpdateParameters>
<asp:Parameter Name="Name" />
<asp:Parameter Name="ID" />
</UpdateParameters>
</asp:SqlDataSource>
</div>
</form>
</body>
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