如何创建文本框列表控件？

Question

I've a textbox for entering employeename.When an user types the employeename,i wanted to list all the employees from database starting with that typed letter,just like a dropdownlist

I dont want any third party control.Is there any easier and understandable way for doing this??

Answer 1

You can use this library it's very easy a with good code

http://www.asp.net/ajaxlibrary/AjaxControlToolkitSampleSite/AutoComplete/AutoComplete.aspx

Answer 2

Firstly we will use Jquery UI Auocomplete that will consume ASP.NET Web Service

(Let's say Name.asmx ).

Add reference to Jquery UI CSS file

<link href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.1/themes/base/jquery-ui.css" rel="stylesheet" type="text/css"/>

Now add reference to Jquery library

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>

Add reference to the Jquery UI

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.1/jquery-ui.min.js"></script> 

Let's say you have a textbox with class auto

<asp:TextBox ID="tbAuto" class="auto" runat="server">
</asp:TextBox>

Now we will write a script that will pass every single letter typed in the textbox to our Web Service (Name.asmx) .

<script type="text/javascript">
$(function() {
    $(".auto").autocomplete({
        source: function(request, response) {
            $.ajax({
                url: "Name.asmx/FetchNames",
                data: "{ 'name': '" + request.term + "' }",
                dataType: "json",
                type: "POST",
                contentType: "application/json; charset=utf-8",
                dataFilter: function(data) { return data; },
                success: function(data) {
                    response($.map(data.d, function(item) {
                        return {
                            value: item.Name
                        }
                    }))
                },
                error: function(XMLHttpRequest, textStatus, errorThrown) {
                    alert(textStatus);
                }
            });
        },
        minLength: 2
    });
});
</script>

Finally here is the Web Service in C#

[WebMethod]
public List<string> FetchNames(string name)
{
//Write your query to get names that begin with the letter passed as parameter and     return results
//Remember return the results by converting it to List.
}

Hope it will help.

Reply in case you have issues.

EDITED:

Here is the query.

SqlDataReader rdr = null;
SqlConnection con = null;
SqlCommand cmd = null;
List<string> empName=new List<string>();

            try
            {
                // Open connection to the database
                string ConnectionString = "server=yourservername;uid=sa;"+
                    "pwd=yourpswd; database=yourdatabase";
                con = new SqlConnection(ConnectionString);
                con.Open();

                // Set up a command with the given query and associate
                // this with the current connection.
                string CommandText = "SELECT FirstName" +
                                     "  FROM Employees" +
                                     " WHERE (FirstName LIKE +name%)";
                cmd = new SqlCommand(CommandText);
                cmd.Connection = con;


                // Execute the query
                rdr = cmd.ExecuteReader();


                while(rdr.Read())
                {
                   empName.Add(rdr["FirstName"].ToString());
                }
              return empName;
            }
            catch(Exception ex)
            {
                // Print error message

            }

Note:I have not tested this , but I think by doing few changes as per your needs it will work fine! Also try and improve this code

Answer 3

you can use jquery autocomplete api :

$(document).ready(function () {
  $("#<%=ApplicationSearchResult.ClientID %>").autocomplete({ //applicationSearchResult is your textbox
  source: function (request, response) {
   $.ajax({
   type: "POST",
   url: "Dashboard.aspx/GetTreeNodesByText", // the function you have to call to bring you the data
   data: "{'text': '" + request.term + "'}", // the letter the user entered in the textbox
   contentType: "application/json; charset=utf-8",
   dataType: "json",
   success: function (data) {
   response(data.d);
   }
   });
   },
   minLength: 1
   });
   });