C#数据库连接

连接SQL2005
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<connectionStrings>
<add Data Source=.;Initial Catalog=User;Integrated Security=True>  //这是用windows身份验证的。“.”代表本机服务器名，“User”表示要连接的数据库名。                  
</add>                                                              //  其中“.”和“True”是固定的。数据库名可以选择自己想要连接的。
</connectionStrings>
</configuration>

用XML来配置好了，把XML文件放在Debug下
<?xml version="1.0" encoding="utf-8"?>
<QC>
  <APP>
    <DATACONNECT comment="数据库连接字符串">Data Source=localhost ;Initial Catalog=CC;User ID=sa;Pwd=123456;Integrated Security=True;</DATACONNECT>
  </APP>
</QC>

我习惯把配置的信息赋值到textBox中，方便后面写，加入有需要，也可以跳过，来连接数据库的时候直接读取XML文件
        private void Form1_Load(object sender, EventArgs e)
        {
            XmlDocument configdoc = new XmlDocument();
            configdoc.Load(Application.StartupPath + "\\config.xml");
            textBox1.Text = configdoc.SelectSingleNode("/QC/APP/DATACONNECT").InnerText;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            SqlConnection connection = null;
            try
            {
                connection = new SqlConnection(textBox1.Text);
                connection.Open();

                SqlCommand command = new SqlCommand();
                command.Connection = connection;
                = "Select * from Gather";
             。。。。。。。
             。。。。。。。
            }