捕獲（失敗）mklink命令輸出

Question

有誰知道爲什麼會發生下面的情況，有沒有人有解決方法？

我strugging捕捉mklink命令輸出（通過cmd.exe的mklink> out.txt）

的輸出被髮送到out.txt細如果mklink命令成功

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

但是，如果命令是無效的，或失敗，那麼什麼都不會被寫入到out.txt

EG：Run above command again（失敗，因爲C：\測試已經存在）或

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

我使用VBScript中的命令，沒有任何人知道如何捕捉mklink輸出如果命令沒有成功完成？

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

（1）根據Using multiple commands and conditional processing symbols，符號&&只運行，如果左側命令成功右邊的命令。即使mlink失敗，您也必須使用& 開始記事本。

（2）雖然mlink docs不說那麼明確，我認爲mlink寫入其錯誤消息到stderr（見here） - 就像dir。

證據：（RSP dir）

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）要捕獲的mlink輸出是否失敗與否，並顯示在記事本中的結果（文件），你必須使用

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

將Stderout 和 Stderr重定向到輸出文件。

證據：

Answer 2

您是否考慮過使用「Exec」命令而不是運行命令並收集輸出結果？

它不需要文件，它更容易。

新代碼

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

舊代碼

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