Private Sub BtnMoveItemstoTemplate_Click(sender As Object, e As EventArgs) Handles BtnMoveItemstoTemplate.Click
Try
If LBMessageContents.SelectedItem Is Nothing Then
ShowMessage("Select Some Details to Send a Message")
Else
RTMsgContent.Text = RTMsgContent.Text & LBMessageContents.SelectedItem
End If
Catch ex As Exception
HandleClassException(ex)
End Try
End Sub
我编写了一个代码,用于将项目从 ListBox 移动到 RichTextBox。
如何验证列表项是否已存在。
最佳答案
正如vinayak所说,您可以使用.contains()
来知道文本框是否包含该字符串
Private Sub BtnMoveItemstoTemplate_Click(sender As Object, e As EventArgs) Handles BtnMoveItemstoTemplate.Click
Try
If LBMessageContents.SelectedItem Is Nothing Then
ShowMessage("Select Some Details to Send a Message")
Else
'check if the item already exists
If RtMsgContent.Text.Contains(LBMessageContents.SelectedItem) then
'do what you want to do if the item already exists. like showing message
MsgBox("Error! This item already exists")
Else
'doesn't already exists, add to the textbox
RTMsgContent.Text = RTMsgContent.Text & LBMessageContents.SelectedItem
End If
End If
Catch ex As Exception
HandleClassException(ex)
End Try
End Sub
关于vb.net - 避免文本框中存在现有项目,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/46235300/