请问关于c的具体应用场景有哪些？

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csharp// 记得使用folderBrowserDialog1和openFileDialog1控件using System.Data.SqlClient;

namespace WindowsApplication1.GoodMethod{ class GetSqlConnection { public static SqlConnection GetSqlConnection() { string sql=DataSource=win7-pc;database=Kc;uid=sa;pwd=sa; SqlConnection SqlCon=new SqlConnection(sql); return SqlCon; } }}

//记得加folderBrowserDialog1openFileDialog1控件

usingSystem.Data.SqlClient;//连接数据库公共变量

namespaceWindowsApplication1.GoodMenhod

{

classgetSqlConnection

{

stringsql="DataSource=win7-pc;database=Kc;uid=sa;pwd=sa";

SqlConnectionconn;

publicSqlConnectionGetCon()

{

conn=newSqlConnection(sql);

conn.Open();

returnconn;

}

}

}

usingSystem.Data.SqlClient;

usingWindowsApplication1.GoodMenhod;//引用命名空间

namespaceWindowsApplication1

{

publicpartialclassForm1:Form

{

publicForm1()

{

InitializeComponent();

}

privatevoidbutton1_Click(objectsender,EventArgse)//打开备份路径

{

if(folderBrowserDialog1.ShowDialog()==DialogResult.OK)

{

txtPath.Text=folderBrowserDialog1.SelectedPath.ToString();

}

}

privatevoidbutton2_Click(objectsender,EventArgse)//备份名称保存

{

try

{

if(txtPath.Text!="")

{

getSqlConnectiongeCon=newgetSqlConnection();

SqlConnectioncon=geCon.GetCon();

stringstrBacl="backupdatabaseKctodisk='"+txtPath.Text.Trim()+"\\"+txtName.Text.Trim()+".bak'";

SqlCommandCmd=newSqlCommand(strBacl,con);

if(Cmd.ExecuteNonQuery()!=0)

{

MessageBox.Show("数据备份成功！","提示框",MessageBoxButtons.OK,MessageBoxIcon.Information);

this.Close();

}

else

{

MessageBox.Show("数据备份失败！","提示框",MessageBoxButtons.OK,MessageBoxIcon.Information);

}

}

else

{

MessageBox.Show("请填写备份的正确位置及文件名！","提示框",MessageBoxButtons.OK,MessageBoxIcon.Information);

}//end

}

catch(Exceptionee)

{

MessageBox.Show(ee.Message.ToString());

}

}

}

}

privatevoidbutton3_Click(objectsender,EventArgse)//打开将要还原的文件

{

openFileDialog1.FilterIndex=0;

openFileDialog1.FileName="";

openFileDialog1.Filter="txtfiles(*.bak)|*.bak|Allfiles(*.*)|*.*";

if(openFileDialog1.ShowDialog()==DialogResult.OK)

{

textPaht.Text=openFileDialog1.FileName.ToString();

}

}

privatevoidbutton4_Click(objectsender,EventArgse)//还原

{

if(textPaht.Text!="")

{

getSqlConnectiongeCon=newgetSqlConnection();

SqlConnectioncon=geCon.GetCon();

if(con.State==ConnectionState.Open)

{

con.Close();

}

//连接的数据库是master,所以要初始化新的连接字符串

stringDateStr="DataSource=win7-pc;Database=master;Userid=sa;PWD=sa";

SqlConnectionconn=newSqlConnection(DateStr);

conn.Open();

//-------------------杀掉所有连接db_CSManage数据库的进程--------------

//stringsql="SELECTspidFROMmaster..sysprocessesWHEREdbid=db_id('"+strDBName+"')";

stringstrSQL="selectspidfrommaster..sysprocesseswheredbid=db_id('Kc')";//读取连接当前数据库的进程

SqlDataAdapterDa=newSqlDataAdapter(strSQL,conn);

DataTablespidTable=newDataTable();

Da.Fill(spidTable);

SqlCommandCmd=newSqlCommand();

Cmd.CommandType=CommandType.Text;

Cmd.Connection=conn;

for(intiRow=0;iRow<=spidTable.Rows.Count-1;iRow++)

{

Cmd.CommandText="kill"+spidTable.Rows[iRow][0].ToString();//强行关闭用户进程

Cmd.ExecuteNonQuery();

}

conn.Close();

conn.Dispose();

//--------------------------------------------------------------------

SqlConnectionsqlcon=newSqlConnection(DateStr);

sqlcon.Open();

SqlCommandsqlCmd=newSqlCommand("backupdatabaseKctodisk='"+textPaht.Text.Trim()+"'restoredatabaseKcfromdisk='"+textPaht.Text.Trim()+"'",sqlcon);

sqlCmd.ExecuteNonQuery();

sqlCmd.Dispose();

sqlcon.Close();

sqlcon.Dispose();

MessageBox.Show("数据还原成功！","提示",MessageBoxButtons.OK,MessageBoxIcon.Information);

MessageBox.Show("为了必免数据丢失，在数据库还原后将关闭整个系统。");

Application.Exit();

}

else

{

MessageBox.Show("请选择备份文件！","提示",MessageBoxButtons.OK,MessageBoxIcon.Warning);

}

}