How to check if programm installed with cmd-CodePudding

@echo off 
color 06
title created by AAIE
@"%SystemRoot%\System32\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -InputFormat None -ExecutionPolicy Bypass -Command "[System.Net.ServicePointManager]::SecurityProtocol = 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))" && SET "PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin"
choco install youtube-dl
set /p input="Enter Link For Playlist:" 
set /p index="Enter Index For videos Seprated by ',':"
mkdir playlist_videos
cd playlist_videos
youtube-dl --playlist-items %index% %input%

how can I check if choco or youtube_dl is installed in windows or not or the main question what is the conditions i need to check if it true then use commands directly if not installed then it will install them and use the same commands

CodePudding user response：

Here are some examples using where to locate and perform actions based on the result:

@echo off
(where choco.exe)>nul 2>&1
if errorlevel 1 (
    echo Choco not installed. Installing now..
    @"%SystemRoot%\System32\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -InputFormat None -ExecutionPolicy Bypass -Command "[System.Net.ServicePointManager]::SecurityProtocol = 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))" && SET "PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin"
)

choco install youtube-dl
set /p input="Enter Link For Playlist:" 
set /p index="Enter Index For videos Seprated by ',':"
mkdir playlist_videos
cd playlist_videos
youtube-dl --playlist-items %index% %input%

or by using conditional operators:

@echo off
(where choco.exe)>nul 2>&1 && goto :installed || goto :install
:install
@"%SystemRoot%\System32\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -InputFormat None -ExecutionPolicy Bypass -Command "[System.Net.ServicePointManager]::SecurityProtocol = 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))" && SET "PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin"

:installed
choco install youtube-dl
set /p input="Enter Link For Playlist:" 
set /p index="Enter Index For videos Seprated by ',':"
mkdir playlist_videos
cd playlist_videos
youtube-dl --playlist-items %index% %input%

Note these are straight forward examples, there are no error handling built in, like what happens if coco install fails, etc.

As per your question on 2>&1 >nul

stdout (seen as 1> when redirecting) is the output stream of a command where stderr (seen as 2> when redirecting.)

When doing >nul or > file.txt we are effectively redirecting the output of a command to nul (not seen on console) or to a file (logging purpose) but not everything goes to the stdout stream by default. so we need to redirect stderr stream to stdout, then redirect stdout to nul or a file.

You can obviously also redirect independently.

commandname 1>out.log 2>error.log