为什么会跳出两个提示框?
Public Class Form1
Private Sub load_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles load.Click, load.Click
Dim Cnn As New ADODB.Connection '定义数据链接对象,保存连接数据库信息;请先添加ADO引用
Dim Rs As New ADODB.Recordset '定义记录集对象,保存数据表
Dim strCnn = "Provider=SQLNCLI;Server=服务大众;Database=qzsyck;Trusted_Connection=yes;"
Cnn.Open(strCnn)
Rs.Open("select * from userpw", Cnn) '定义SQL查询命令字符串
Dim loadTF As Integer
loadTF = 0
'循环
Do Until Rs.EOF
If (Rs("user").Value.trim().Equals(user.Text()) And Rs("password").Value.trim().Equals(password.Text())) Then
loadTF = 1
End If
Rs.MoveNext()
Loop
If loadTF = 1 Then
MsgBox("登录成功")
Else
MsgBox("登录失败")
End If
Rs.Close()
Cnn.Close()
End Sub
End Class
代码如上,为什么会重复跳出两个提示框?比如输入正确的用户名密码,提示登录成功,但是却是跳出两遍,反之,登录失败,一样跳出两次提示框??奇怪!!
[解决办法]
Do循环中 loadTF = 1 的下面加上一句:exit do
[解决办法]
上下各加一句,然后测试,怀疑你的鼠标有问题。
- VB.NET code
Private Sub load_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles load.Click load.Enabled = False ' '你的语句 ' load.Enabled = True End Sub
[解决办法]
If loadTF = 1 Then
MsgBox("登录成功")
exit do
Else
MsgBox("登录失败")
exit do
End If
这样改试试
[解决办法]
这2行Rs.Close(),Cnn.Close()放到If loadTF = 1 Then的前面试试
[解决办法]
代码看起来没问题,其实调试一下就知道了,看2次弹出代码是怎么运行顺序的。
[解决办法]
[解决办法]
- VB.NET code
'Private Sub load_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles load.Click, load.Click 改为:Private Sub load_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles load.Click