//app.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration><startup> <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" /></startup><connectionStrings><add name="dbConnStr" connectionString="Data Source=服务器地址;Initial Catalog=数据库;User ID=账号（可以是sa）;Password=密码"/></connectionStrings>
</configuration>

//content

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;namespace DataBaseTest
{/// <summary>/// MainWindow.xaml 的交互逻辑/// </summary>public partial class MainWindow : Window{public MainWindow(){InitializeComponent();}private void Button_Click_1(object sender, RoutedEventArgs e){using (SqlConnection conn = new SqlConnection("Data Source=xxx;Initial Catalog=xxx;User ID=sa;Password=xxx")){conn.Open();using(SqlCommand cmm = conn.CreateCommand()){//cmm.CommandText = "select * from T_Student";//没有返回值//cmm.ExecuteNonQuery();//有一个返回值//insert into T_Student(Name,Age) output inserted.Id values （'aaa',123）;// object o = cmm.ExecuteScalar();//多个返回值//using (SqlDataReader reader = cmm.ExecuteReader())//{//    while(reader.Read())//    {//        MessageBox.Show(reader.GetString(1));//    }//}cmm.CommandText = "select * from T_Student where Name=@Name";cmm.Parameters.Add(new SqlParameter("@Name", txtSearch.Text));//查询输入内容using (SqlDataReader reader = cmm.ExecuteReader()){while (reader.Read()){MessageBox.Show(reader.GetString(1));}}}}MessageBox.Show("successful");}private void 离线数据集_Click(object sender, RoutedEventArgs e){using (SqlConnection conn = new SqlConnection("Data Source=xxx;Initial Catalog=xxxx;User ID=sa;Password=xxx")){conn.Open();using (SqlCommand cmm = conn.CreateCommand()){cmm.CommandText = "select * from T_Student where Name=@Name";cmm.Parameters.Add(new SqlParameter("@Name", txtSearch.Text));//SqlDataAdapter是一个把查询结果填充到DataSet中SqlDataAdapter adapt = new SqlDataAdapter(cmm);//本地集合DataSet dataset = new DataSet();adapt.Fill(dataset);DataTable table = dataset.Tables[0];DataRowCollection rows = table.Rows;for (int i = 0; i < rows.Count; i++){DataRow row = rows[i];int age = (int)row["Age"];string name = (string)row["Name"];MessageBox.Show("name: "+name+" age: "+age);}}}}private void btnConStr_Click(object sender, RoutedEventArgs e){//需要添加system.Configration referencestring connStr = ConfigurationManager.ConnectionStrings["dbConnStr"].ConnectionString;MessageBox.Show(connStr);//SqlHelper.ExecuteNonQuery("insert into T_Student(Name,Age) values ('eee',123)");MessageBox.Show("succeed insert");//DataSet dataset = new DataSet();//using (SqlConnection conn = new SqlConnection(connStr))//{//    conn.Open();//    using (SqlCommand cmm = conn.CreateCommand())//    {//        cmm.CommandText = "select * from T_Student where Name=@Name";//        cmm.Parameters.Add(new SqlParameter("@Name", txtSearch.Text));//        //SqlDataAdapter是一个把查询结果填充到DataSet中//        SqlDataAdapter adapt = new SqlDataAdapter(cmm);//        //本地集合//        adapt.Fill(dataset);//        DataTable table = dataset.Tables[0];//        DataRowCollection rows = table.Rows;//        for (int i = 0; i < rows.Count; i++)//        {//            DataRow row = rows[i];//            int age = (int)row["Age"];//            string name = (string)row["Name"];//            MessageBox.Show("name: " + name + " age: " + age);//        }//    }//}}private void Button_Click_2(object sender, RoutedEventArgs e){//DataSet ds = SqlHelper.ExecuteDataSet("select * from T_Student");//foreach (DataRow row in ds.Tables[0].Rows)//{//    string name = (string)row["Name"];//    MessageBox.Show(name);//}DataTable ds = SqlHelper.ExecuteDataTable("select * from T_Student");foreach (DataRow row in ds.Rows){string name = (string)row["Name"];MessageBox.Show(name);}}}
}