UC知道vb.net的一些问题
来源：百度知道 编辑：UC知道 时间：2024/07/07 09:11:19
Private Sub Form3_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim conn As New OleDb.OleDbConnection
conn.ConnectionString = "Provider=SQLOLEDB.1"
Dim com As New OleDb.OleDbCommand("select course from course order by c_id", conn)
Dim dr As OleDb.OleDbDataReader
Dim course As String
conn.open()
dr = com.ExecuteReader()
While dr.Read()
course = Trim(dr.GetString(0))
ComboBox1.Items.Add(course)
End While
dr.Close()
com.Dispose()
conn.close()
这段代码有什么错误吗？
为什么总是提示“未处理的“System.Data.OleDb.OleDbException”类型的异常出现在 system.data.dll 中。”
你改了哪里？
能说的再具体点吗？
Dim conn As New OleDb.OleDbConnection
conn.ConnectionString = "Provider=SQLOLEDB.1"
Dim com As New OleDb.OleDbCommand("select course from course order by c_id", conn)
Dim dr As OleDb.OleDbDataReader
Dim course As String
conn.open()
dr = com.ExecuteReader()
While dr.Read()
course = Trim(dr.GetString(0))
ComboBox1.Items.Add(course)
End While
dr.Close()
com.Dispose()
conn.close()
这段代码有什么错误吗？
为什么总是提示“未处理的“System.Data.OleDb.OleDbException”类型的异常出现在 system.data.dll 中。”
你改了哪里？
能说的再具体点吗？
不知道你为什么会出问题,我试了一下,将你的代码改了一点,调试没有出现问题.如果你的数据库连接不会有问题,应该是可以运行的.
Dim conn As New OleDb.OleDbConnection
conn.ConnectionString = "Provider=SQLOLEDB.1; Data Source=192.168.1.177; uid=sa; pwd=; Initial Catalog=tempdb"
Dim com As New OleDb.OleDbCommand("select name from sysusers order by uid", conn)
Dim dr As OleDb.OleDbDataReader
Dim course As String
conn.Open()
dr = com.ExecuteReader()
While dr.Read()
course = Trim(dr.GetString(0))
Console.Write(course)
End While
dr.Close()
com.Dispose()
conn.Close()