捕获（失败）mklink命令输出

Question

有人知道为什么会发生以下情况并且有人有解决方法吗？

我正在捕捉mklink命令输出（通过cmd.exe mklink＆gt; out.txt）

如果mklink命令成功，输出将被发送到out.txt

E.G：%comspec% /c mklink /d C:\Test C:\Windows > out.txt && notepad out.txt

但是，如果命令无效或失败，则不会将任何内容写入out.txt

E.G：Run above command again（因为C：\ Test已经存在而失败）或

E.G：%comspec% /c mklink > out.txt && notepad out.txt

我在VBScript中使用该命令，如果命令没有成功完成，有人知道如何捕获mklink输出吗？

Set o_shell = CreateObject("Wscript.Shell")
Set o_fso = CreateObject("Scripting.FileSystemObject")
mklinkCommandOutput = GetCommandOutput("mklink /D ""C:\Test"" ""C:\Windows""")
WScript.echo mklinkCommandOutput

Function GetCommandOutput(runCmd)
  on error resume next
  Dim o_file, tempFile: tempFile = o_shell.ExpandEnvironmentStrings("%TEMP%") & "\tmpcmd.txt"

  ' Run command and write output to temp file
  o_shell.Run "%COMSPEC% /c " & runCmd & " > """ & tempFile & """", 0, 1

  ' Read command output from temp file
  Set o_file = o_fso.OpenTextFile(tempFile, 1)
  GetCommandOutput = o_file.ReadAll
  o_file.Close

  ' Delete temp file
  Set o_file = o_fso.GetFile(tempFile)
  o_file.Delete
End Function

Answer 1

您是否考虑过使用＆＃34; Exec＆＃34;命令而不是运行命令并收集输出结果？

它不需要文件，而且它更容易。

新代码

Function GetCommandOutput(runCmd)
  Dim WshShell, oExec
  Set WshShell = CreateObject("WScript.Shell")
  Set oExec    = WshShell.Exec("%COMSPEC% /c " & runCmd)
  GetCommandOutput = oExec.StdOut.ReadAll
End Function 

旧代码

Function GetCommandOutput(runCmd)
  on error resume next
  Dim o_file, tempFile: tempFile = o_shell.ExpandEnvironmentStrings("%TEMP%") & "\tmpcmd.txt"

  ' Run command and write output to temp file
  o_shell.Run "%COMSPEC% /c " & runCmd & " > """ & tempFile & """", 0, 1

  ' Read command output from temp file
  Set o_file = o_fso.OpenTextFile(tempFile, 1)
  GetCommandOutput = o_file.ReadAll
  o_file.Close

  ' Delete temp file
  Set o_file = o_fso.GetFile(tempFile)
  o_file.Delete
End Function 

Answer 2

（1）根据Using multiple commands and conditional processing symbols，符号&&仅在左侧的命令成功时才在右侧运行命令。你必须使用& 即使mlink失败，也要开始记事本。

（2）虽然mlink docs没有明确说明，但我认为mlink将其错误消息写入Stderr（请参阅here） - 就像dir一样

证据：

dir 01.vbs
...
19.10.2012  11:29             2.588 01.vbs
...
(dir succeeded)

dir nix
...
File Not Found
(dir failed)

dir nix && echo nothing to see, because lefty failed
...
File Not Found
(dir failed, no output because of &&)

dir nix & echo much to see, although lefty failed
...
File Not Found
much to see, although lefty failed
(dir succeeded, echo done because of &)

（3）要捕获mlink（rsp。dir）的输出是否失败并在记事本中显示结果（文件），你必须使用

dir 01.vbs 1> out.txt 2>&1 & notepad out.txt
dir nix 1> out.txt 2>&1 & notepad out.txt

将Stdout 和 Stderr重定向到输出文件。

证据：