ConfigurationManager.ConnectionStrings 属性[通俗易懂]

public static ConnectionStringSettingsCollection ConnectionStrings { get; }

App.config

1 <?xml version="1.0" encoding="utf-8" ?>
2 <configuration>
3     <startup> 
4         <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
5     </startup>
6     <connectionStrings>
7       <add name="WingtipToys" connectionString="Data Source=(LocalDB)\v11.0;Initial Catalog=WingtipToys;Integrated Security=True;
Pooling=False" />
8     </connectionStrings>
9 </configuration>

如何使用连接字符串从数据库读取数据。

 1 using System;
 2 using System.Configuration;
 3 using System.Data.SqlClient;
 4 
 5 namespace ConsoleApplication1
 6 {
 7     class Program
 8     {
 9         static void Main(string[] args)
10         {
11             ReadProducts();
12         }
13 
14         static void ReadProducts()
15         {
16             var connectionString = ConfigurationManager.ConnectionStrings["WingtipToys"].ConnectionString;
17             string queryString = "SELECT Id, ProductName FROM dbo.Products;";
18             using (var connection = new SqlConnection(connectionString))
19             {
20                 var command = new SqlCommand(queryString, connection);
21                 connection.Open();
22                 using (var reader = command.ExecuteReader())
23                 {
24                     while (reader.Read())
25                     {
26                         Console.WriteLine(String.Format("{0}, {1}", reader[0], reader[1]));
27                     }
28                 }
29             }
30         }
31     }
32 }