vb.net 如何检测文件是否未找到
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How to detect if file isn't found
提问by user1877499
I'm a bit new to VB.NET. I was wondering if there was a way to detect if a file being open doesn't exist, then something will happen. Is this possible and is it possible using the "If" statement?
我对 VB.NET 有点陌生。我想知道是否有办法检测打开的文件是否不存在，然后会发生一些事情。这是可能的，是否可以使用“If”语句？
回答by xpda
You can use file.exists(filename)to check before you open it, or a try-catch block:
您可以file.exists(filename)在打开它之前使用to check 或 try-catch 块：
If not System.IO.File.Exists(filename) Then
' file does not exist
end if
or
或者
Try
open ...
Catch ex As Exception
MsgBox(ex.Message) ' not-found error handling goes here
End Try
You can add imports system.ioat the top of your file to use File.Existsinstead of System.IO.File.Exists.
您可以imports system.io在文件顶部添加以File.Exists代替System.IO.File.Exists.
