c#配置文件的简单操作

// 配置文件
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<appSettings>
<!-- 配置文件，连接数据库字符串 -->
<add key="myconn" value="server=.;database=students; uid=sa;pwd=123456" />
</appSettings>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5"/>
</startup>
</configuration>

// form文件
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Configuration;
using System.Data.SqlClient;

namespace myConfig
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void bt_Data_Click(object sender, EventArgs e)
{
// 获取连接字符串信息
string connstr = ConfigurationManager.AppSettings["myconn"];
using (SqlConnection conn = new SqlConnection(connstr))
{
conn.Open();
string strcmd = "select * from stu;";
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(strcmd,connstr);
da.Fill(ds,"MyTable");
dgv_Data.DataSource = ds.Tables["MyTable"];
}
}
}
}