ADO.NET中SQL Command的执行

在项目里加入配置文件：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<connectionStrings>
<add name ="Students"
providerName ="System.Data.SqlClient"
connectionString ="server=(local); integrated security = SSPI;
database = Students"/>
</connectionStrings>
</configuration>

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下面的代码里，包括如何引用配置文件的连接字符串，以及SQL Command执行的四种方法：

注意：system.configuration system.Transaction需要手动加入Reference

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.Common;
using System.Configuration;
using System.Data.SqlClient;
using System.Transactions;
using System.Xml;

namespace SQLConnDemo
{
class Program
{
private DbConnection GetDatabaseConnection(string name)
{
ConnectionStringSettings settings = ConfigurationManager.ConnectionStrings[name];

DbProviderFactory factory = DbProviderFactories.GetFactory(settings.ProviderName);

DbConnection conn = factory.CreateConnection();
conn.ConnectionString = settings.ConnectionString;

return conn;
}

private static string GetConnectionStringsConfig(string connectionName)
{
string connectionString = ConfigurationManager.ConnectionStrings[connectionName].ConnectionString.ToString();
Console.WriteLine(connectionString);
return connectionString;
}

static void Main(string[] args)
{
string source = GetConnectionStringsConfig("Students");

try
{
using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required))
{
using (SqlConnection conn = new SqlConnection(source))
{
// Open the connenction
conn.Open();

// ExecuteNonQuery Method Applies to Update, Insert, Delete SQL statement
string strUpdate = "UPDATE XS " + "SET 备注 = '已提前修完一门课，并获得学分' " + "Where 姓名 = '罗琳琳'";
SqlCommand cmd = new SqlCommand(strUpdate, conn);
int rowReturned = cmd.ExecuteNonQuery();
Console.WriteLine("{0} rows returned", rowReturned);

// ExecuteReader Method
string strSelect = "SELECT 学号,备注 FROM XS";
SqlCommand cmd2 = new SqlCommand(strSelect, conn);
SqlDataReader reader = cmd2.ExecuteReader();
while (reader.Read())
{
Console.WriteLine("Student ID: {0}", reader[0]);
}
reader.Close();

// ExecuteScalar Method
string countselect = "SELECT COUNT(*) FROM XS";
SqlCommand cmd3 = new SqlCommand(countselect, conn);
Object o = cmd3.ExecuteScalar();
Console.WriteLine(o);

// ExecuteXmlReader Method
string strXmlSelect = "SELECT 学号,备注 FROM XS" + " FOR XML AUTO";
SqlCommand cmd4 = new SqlCommand(strXmlSelect, conn);
XmlReader xr = cmd4.ExecuteXmlReader();
xr.Read();
string data;
do
{
data = xr.ReadOuterXml();
if (!string.IsNullOrEmpty(data))
Console.WriteLine(data);
} while (!string.IsNullOrEmpty(data));
xr.Close();

// Do something useful

//Mark complete
scope.Complete();

// Close the connection
conn.Close();
}
}
}
catch(SqlException ex)
{
// Log the exception
Console.WriteLine(ex.Message);
}
}
}
}

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background-color: #ffffff;
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.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
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.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
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.csharpcode .lnum { color: #606060; }