奇怪,数据库操作,为什么有些代码没有运行?
初学者,代码难看,莫怪.
我标记的代码运行不到,没有输出,好奇怪呀.有没有人帮解释一下.谢谢!!
public class TestCode断点调试下
{
private static List<string> ids = new List<string>();
private static List<string> names = new List<string>();
private static string myConnstr;
private static OleDbConnection myconn; // 数据库连接
private static string mysql; // 数据库操作语句
private static OleDbCommand mycommand = new OleDbCommand();
private static string dbpath; // 数据库名
private static int InsertStartId;
// 初始化数据库.
private static void initdatabase()
{
dbpath = "oledb.mdb";
myConnstr =
@"Provider=Microsoft.Jet.OleDB.4.0;Data Source=" +
dbpath;
}
// 查询数据库
private static void findall()
{
ids.Clear();
names.Clear();
mysql = @"select id,user_name from users"; // 操作
using (myconn)
{
myconn = new OleDbConnection(myConnstr);
myconn.Open();
mycommand.CommandText = mysql;
mycommand.Connection = myconn;
OleDbDataReader myreader = mycommand.ExecuteReader();
int i = 0;
while (myreader.Read())// 读取
{
ids.Add(myreader["id"].ToString());
names.Add(myreader["user_name"].ToString());
i++;
}
/***********这里好像没有运行*********************/
InsertStartId = i + 1;
Console.WriteLine("Strat ID is: " + InsertStartId.ToString());
/***********这里好像没有运行*********************/
myconn.Close();
myreader.Close();
}
}
// 插入数据库数据.
private static bool insert()
{
mysql =
@"insert into users Values(
'" + InsertStartId.ToString() + @"',
'insert" + InsertStartId.ToString() + @"')";
using (myconn)
{
myconn = new OleDbConnection(myConnstr);
myconn.Open();
mycommand.CommandText = mysql;
mycommand.Connection = myconn;
if(mycommand.ExecuteNonQuery() > 0)
{
return true;
}
else
return false;
}
}
public static void Main()
{
// ToDo: type todo code here;
initdatabase();
while(true)
{
findall();
foreach (string _name in names)
{
Console.WriteLine(_name);
}
Console.WriteLine("Press Any Key To Insert!");
Console.ReadKey();
if(insert())
{
Console.WriteLine("Insert" + InsertStartId + "'th Data Success!!");
Console.WriteLine("Press Any Key To List Result!");
Console.ReadKey();
}
}
}
