C# 为什么赢了';我的查询没有运行吗?
我有很多类似的问题都能解决,我不知道为什么这个问题不能解决: 我一运行它,就会得到: 类型的未处理异常 中出现“System.Data.SqlServerCe.SqlCeException” System.Data.SqlServerCe.dll …在C# 为什么赢了';我的查询没有运行吗?,c#,sql,sql-server-ce,C#,Sql,Sql Server Ce,我有很多类似的问题都能解决,我不知道为什么这个问题不能解决: 我一运行它,就会得到: 类型的未处理异常 中出现“System.Data.SqlServerCe.SqlCeException” System.Data.SqlServerCe.dll …在命令.ExecuteNonQuery()上 有什么明显的失误吗 public void BorrowMovie(int memberCardNumber) { string connectionString = @"Data Source=
命令.ExecuteNonQuery()上代码>
有什么明显的失误吗
public void BorrowMovie(int memberCardNumber)
{
string connectionString = @"Data Source=|DataDirectory|\VideoStoreDB.sdf";
SqlCeConnection connection = new SqlCeConnection(connectionString);
connection.Open();
SqlCeCommand command = new SqlCeCommand(
"UPDATE Customer SET NumberBorrowedMovies = NumberBorrowedMovies+1 " +
"WHERE MemberCardNR = @mcn)", connection);
command.Parameters.AddWithValue("@mcn", memberCardNumber);
command.ExecuteNonQuery();
connection.Close();
Console.WriteLine("Movie was borrowed!");
Console.ReadLine();
}
您有不平衡的括号:
SqlCeCommand command = new SqlCeCommand(
"UPDATE Customer SET NumberBorrowedMovies = NumberBorrowedMovies+1 " +
"WHERE MemberCardNR = @mcn", connection);
此外,您应该使用使用块:
public void BorrowMovie(int memberCardNumber)
{
string connectionString = @"Data Source=|DataDirectory|\VideoStoreDB.sdf";
using (SqlCeConnection connection = new SqlCeConnection(connectionString))
{
connection.Open();
using (SqlCeCommand command = new SqlCeCommand(
"UPDATE Customer SET NumberBorrowedMovies = NumberBorrowedMovies+1 " +
"WHERE MemberCardNR = @mcn)", connection))
{
command.Parameters.AddWithValue("@mcn", memberCardNumber);
command.ExecuteNonQuery();
// connection.Close(); no longer needed
} // command
} // connection
Console.WriteLine("Movie was borrowed!");
Console.ReadLine();
}
您有不平衡的括号:
SqlCeCommand command = new SqlCeCommand(
"UPDATE Customer SET NumberBorrowedMovies = NumberBorrowedMovies+1 " +
"WHERE MemberCardNR = @mcn", connection);
此外,您应该使用使用块:
public void BorrowMovie(int memberCardNumber)
{
string connectionString = @"Data Source=|DataDirectory|\VideoStoreDB.sdf";
using (SqlCeConnection connection = new SqlCeConnection(connectionString))
{
connection.Open();
using (SqlCeCommand command = new SqlCeCommand(
"UPDATE Customer SET NumberBorrowedMovies = NumberBorrowedMovies+1 " +
"WHERE MemberCardNR = @mcn)", connection))
{
command.Parameters.AddWithValue("@mcn", memberCardNumber);
command.ExecuteNonQuery();
// connection.Close(); no longer needed
} // command
} // connection
Console.WriteLine("Movie was borrowed!");
Console.ReadLine();
}
InnerException
是什么意思?西蒙,请原谅,我还不知道InnerException是什么。。。我是C#和visual studio的新手@Simon Whitehead。希望这是InnerExeption
:解析查询时出错。[Token line number=1,Token line offset=92,Token in error=>]
@SimonWhitehead:)如何找到@paqogomez,这是VB.Net的…:)InnerException
是什么意思?西蒙,请原谅,我还不知道InnerException是什么。。。我是C#和visual studio的新手@Simon Whitehead。希望这是InnerExeption
:解析查询时出错。[Token line number=1,Token line offset=92,Token in error=>]
@SimonWhitehead:)如何找到@paqogomez,这是VB.Net的…:)哦,哇。。根本看不出来!哦,来吧……(恨我自己)非常感谢你,约翰!我为什么要用积木@John Saundersf为了获得额外的学分,请回答以下问题:“内部异常”说了什么?提示:仅用于故障排除目的:捕获异常,用ex.ToString()
显示它,以防止资源泄漏。噢,哇。。根本看不出来!哦,来吧……(恨我自己)非常感谢你,约翰!我为什么要用积木@John Saundersf为了获得额外的学分,请回答以下问题:“内部异常”说了什么?提示:仅用于故障排除目的:捕获异常,用ex.ToString()
显示它以防止资源泄漏。