ASP.NET Tutorial/Configuration/ConfigurationManager
Load connection string from ConfigurationManager
<source lang="csharp">
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="FromConfig" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server">
<title>Connection String from Config</title>
</head> <body>
<form id="form1" runat="server">
<asp:Button ID="Button1" runat="server" Text="Go get data..." OnClick="Button1_Click" />
<asp:DropDownList runat="server" ID="CustomerList" />
</form>
</body> </html> File: Default.aspx.cs using System; using System.Data; using System.Configuration; using System.Data.SqlClient; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; public partial class FromConfig : System.Web.UI.Page {
protected void Button1_Click(object sender, EventArgs e)
{
string connString = ConfigurationManager.ConnectionStrings["LocalNWind"].ConnectionString;
using (SqlConnection conn = new SqlConnection(connString))
{
string cmdText = "SELECT * FROM customers";
SqlCommand cmd = new SqlCommand(cmdText, conn);
cmd.Connection.Open();
SqlDataReader reader = cmd.ExecuteReader();
CustomerList.Items.Clear();
while (reader.Read())
CustomerList.Items.Add(reader["companyname"].ToString());
reader.Close();
cmd.Connection.Close();
}
}
} File: Web.config <?xml version="1.0"?> <configuration> ...
<connectionStrings> <add name="LocalNWind" connectionString="SERVER=(local);DATABASE=northwind;Trusted_Connection=yes;" /> </connectionStrings>
... </configuration></source>
