WPF中SqlHelper

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using System.Configuration; 
using System.Data; 
using System.Data.SqlClient; 
namespace 数据绑定 
{ 
    class SqlHelper 
    { 
        private static string strconn= ConfigurationManager.ConnectionStrings["dbstrConn"].ConnectionString; 
        public static int ExecuteNonQuery(string sql) 
        { 
            using (SqlConnection conn = new SqlConnection(strconn)) 
            { 
                conn.Open(); 
                using (SqlCommand cmd = conn.CreateCommand()) 
                { 
                    cmd.CommandText = sql; 
                    return cmd.ExecuteNonQuery(); 
                } 
                 
            } 
        } 
        public static object ExecuteScalar(string sql) 
        { 
            using (SqlConnection conn = new SqlConnection(strconn)) 
            { 
                conn.Open(); 
                using (SqlCommand cmd = conn.CreateCommand()) 
                { 
                    cmd.CommandText = sql; 
                    return cmd.ExecuteScalar(); 
                } 
 
            } 
        } 
        //查询少量数据 
        public static DataTable ExecuteTable(string sql) 
        { 
            using (SqlConnection conn = new SqlConnection(strconn)) 
            { 
                conn.Open(); 
                using (SqlCommand cmd = conn.CreateCommand()) 
                { 
                    cmd.CommandText = sql; 
                    SqlDataAdapter adapter = new SqlDataAdapter(cmd); 
                    DataSet dataset = new DataSet(); 
                    adapter.Fill(dataset); 
                    return dataset.Tables[0];    
                } 
 
            } 
        } 
    } 
}