数据访问-----ADO.NET 练习2
一、向Info中插入数据。
1.从界面输入信息。
2.输入内容的检查：基本格式的检查，主外键的检查。
3.执行插入
class Program
{
//定义常量
public const string CONNECTIONSTRING = "server=.;database=mydb;uid=sa;pwd=5587725";
//检查格式
public static bool check(string ColumnName,string value)
{
if (ColumnName=="sex")
{
if (value=="0"||value=="1")
{
return true;
}
else
{
return false;
Console.WriteLine("输入的性别格式不正确");
}
}
else if (ColumnName=="Birthday")
{
try
{
Convert.ToDateTime(value);
return true;
}
catch
{
Console.WriteLine("生日格式不正确");
return false;
}
}
else
{
return true;
}
}
//检查主键
public static bool checkPK(string pk)
{
bool HasPk = true;
SqlConnection conn = new SqlConnection(CONNECTIONSTRING);
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "select * from info where code='"+pk+"'";
SqlDataReader dr = cmd.ExecuteReader();
if (dr.HasRows)
{
HasPk = false;
Console.WriteLine("主键已存在");
}
else
{
HasPk = true;
}
conn.Close();
return HasPk;
}
//检查民族
public static bool checkNation(string nation)
{
bool HasNation = true;
SqlConnection conn = new SqlConnection(CONNECTIONSTRING);
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "select * from info where nation='"+nation+"'";
SqlDataReader dr = cmd.ExecuteReader();
if (dr.HasRows)
{
HasNation = true;
}
else
{
Console.WriteLine("民族代号输入不正确");
HasNation = false;
}
conn.Close();
return HasNation;
}
//检查综合
public static bool checkPut(string code,string sex,string nation,string birthday)
{
//检查
//1.对输入的数据格式检查
bool isOK = true;
bool isOK1 = check("Sex", sex);
bool isOK2 = check("Birthday", birthday);
//2.对主外键的检查
bool isOK3 = checkPK(code);
bool isOK4 = checkNation(nation);
isOK = isOK && isOK1 && isOK2 && isOK3 && isOK4;
return isOK;
}
//插入
public static void ADDinfo(string code,string name,string sex,string nation,string birthday)
{
SqlConnection conn = new SqlConnection(CONNECTIONSTRING);
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "insert into info values('"+code+"','"+name+"','"+sex+"','"+nation+"','"+birthday+"')";
cmd.ExecuteNonQuery();
conn.Close();
}
static void Main(string[] args)
{
//输入
Console.Write("代号：");
string code = Console.ReadLine();
Console.Write("姓名：");
string name = Console.ReadLine();
Console.Write("性别（0-女，1-男）：");
string sex = Console.ReadLine();
Console.Write("民族：");
string nation = Console.ReadLine();
Console.Write("生日：");
string birthday = Console.ReadLine();
//检查
bool isOK = checkPut(code,sex,nation,birthday);
//插入
if（isOK==true）
{
ADDinfo(code, name, sex, nation, birthday);
}
}
}
二、从Info表中删除数据。
1.显示信息
2.输入要删除的主键
3.检查输入的主键是否存在。
4.执行删除（外键的情况——数据库中使用级联删除解决；写代码先删从表最后删除主表来解决。）
5.显示信息
class Program
{
public const string CONCNNECTIONSTRING = "server=.;database=mydb;uid=sa;pwd=5587725";
//显示所有人员信息
public static string GETnation(string code)
{
string str = "";
SqlConnection conn = new SqlConnection(CONCNNECTIONSTRING);
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "select *from nation where code='"+code+"'";
SqlDataReader dr = cmd.ExecuteReader();
if (dr.HasRows)
{
dr.Read();
str = dr["name"].ToString();
}
else
{
str = "";
}
conn.Close();
return str;
}
public static void show()
{
SqlConnection conn = new SqlConnection(CONCNNECTIONSTRING);
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText="select * from info";
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
string code = dr["code"].ToString() ;
string name = dr["name"].ToString() ;
string sex = ((bool)dr["sex"])?"男":"女" ;
string nation = GETnation(dr["nation"].ToString()) ;
string birthday = ((DateTime)dr["birthday"]).ToString("yyyy年MM月dd日") ;
Console.WriteLine(code+ "\t"+name+ "\t"+sex+ "\t"+nation+ "\t"+birthday+ "\n");
}
conn.Close();
}
//检查主键是否存在
public static bool checkPK(string pk)
{
bool HasPK = true;
SqlConnection conn = new SqlConnection(CONCNNECTIONSTRING);
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "select * from info where code='"+pk+"'";
SqlDataReader dr = cmd.ExecuteReader();
HasPK = dr.HasRows;
conn.Close();
return HasPK;
}
//删除
public static void Deleteinfo(string pk)
{
SqlConnection conn = new SqlConnection(CONCNNECTIONSTRING);
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "delete from work where infocode='" + pk + "'";
cmd.ExecuteNonQuery();
cmd.CommandText = "delete from family where infocode='" + pk + "'";
cmd.ExecuteNonQuery();
cmd.CommandText = "delete from info where code='"+pk+"'";
cmd.ExecuteNonQuery();
conn.Close();
}
static void Main(string[] args)
{
//显示
show();
//输入要删除的主键
Console.WriteLine("请输入你要删除的人员代码：");
string code = Console.ReadLine();
//检查输入的主键是否存在
bool isOK = checkPK(code);
//删除
if (isOK==true)
{
Deleteinfo(code);
Console.WriteLine("删除成功");
}
else
{
Console.WriteLine("找不到要删除的人员代号，删除失败，请重新检查要删除的人员代号。");
}
//显示
show();
Console.ReadLine();
}