请高手进来看一下,俺马上就要交课程设计了,关于update 更新数据库记录的问题!

[nhwm]

代码如下:
Sub Button1_Click(sender As Object, e As EventArgs)
dim s_no as string ="20017400111"
dim count as integer =15
dim flag as integer= MyUpdateMethod(s_no,count)
response.write(flag)
End Sub


Function MyUpdateMethod(ByVal s_no As String, ByVal count As Integer) As Integer
Dim connectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0; Ole DB Services=-4; Data Source=D:\asp.net\desi"& _
"gn\database.mdb"
Dim dbConnection As System.Data.IDbConnection = New System.Data.OleDb.OleDbConnection(connectionString)

Dim queryString As String = "UPDATE [student_info] SET [已选门数]=@count WHERE ([student_info].[学号] = @s_no)"
Dim dbCommand As System.Data.IDbCommand = New System.Data.OleDb.OleDbCommand
dbCommand.CommandText = queryString
dbCommand.Connection = dbConnection

Dim dbParam_s_no As System.Data.IDataParameter = New System.Data.OleDb.OleDbParameter
dbParam_s_no.ParameterName = "@s_no"
dbParam_s_no.Value = s_no
dbParam_s_no.DbType = System.Data.DbType.String
dbCommand.Parameters.Add(dbParam_s_no)
Dim dbParam_count As System.Data.IDataParameter = New System.Data.OleDb.OleDbParameter
dbParam_count.ParameterName = "@count"
dbParam_count.Value = count
dbParam_count.DbType = System.Data.DbType.Int32
dbCommand.Parameters.Add(dbParam_count)

Dim rowsAffected As Integer = 0
dbConnection.Open
Try
rowsAffected = dbCommand.ExecuteNonQuery
Finally
dbConnection.Close
End Try

Return rowsAffected
End Function

语句正常执行后,满足条件的数据库记录的 已选门数 字段值无变化!
望高手给出正确的源代码!

[cpp2017]

把Try语句去掉后看有没有出错,

[zldcolin]

把try--catch去掉看看错误信息
贴出来看看

[huangsuipeng]

rowsAffected = dbCommand.ExecuteNonQuery后
rowsAffected 值是多少？

[huangsuipeng]

因为dbParam_s_no.DbType = System.Data.DbType.String

试把
Dim queryString As String = "UPDATE [student_info] SET [已选门数]=@count WHERE ([student_info].[学号] = @s_no)"
改为
Dim queryString As String = "UPDATE [student_info] SET [已选门数]=@count WHERE ([student_info].[学号] =‘ @s_no ’)"

[nhwm]

还是要不得啊,请大家帮忙啊,下午就要交了!!

[guxiangdefeng]

先把数据代进去,把SQL语句放到SQL的查询分析器里执行看看,如果不更新,说明SQL语句有问题.
否则是程序的问题,把try catch去掉,用断点跟