How to Download Files in PowerShell with Code Examples
PowerShell is a powerful and flexible scripting language that can be used for a variety of tasks, including file management. In this article, we'll explore how to download files using PowerShell, including both single and multiple files.
Single File Download
The simplest way to download a file in PowerShell is to use the Invoke-WebRequest cmdlet. This cmdlet is available in PowerShell versions 3.0 and later. To use this cmdlet, you'll need to provide the URL of the file you want to download and specify the file path where you want to save the downloaded file.
Here's an example of how to download a file from the internet using Invoke-WebRequest:
Invoke-WebRequest -Uri "https://example.com/file.zip" -OutFile "C:\Downloads\file.zip"
In this example, we're downloading the file "file.zip" from the URL "https://example.com/file.zip" and saving it to the "C:\Downloads" directory on our local computer.
Multiple File Downloads
If you need to download multiple files, you can use a loop to download each file one at a time. Here's an example of how to download multiple files using a foreach loop:
$files = @("https://example.com/file1.zip", "https://example.com/file2.zip", "https://example.com/file3.zip")
foreach ($file in $files) {
Invoke-WebRequest -Uri $file -OutFile "C:\Downloads\$(Split-Path $file -Leaf)"
}
In this example, we've created an array of file URLs and then used a foreach loop to download each file. The Split-Path cmdlet is used to extract the file name from the URL so that we can use it as the file name when saving the downloaded file.
Downloading with Progress Bar
Sometimes you may want to see the progress of a file download. To display a progress bar while downloading a file, you can use the Start-BitsTransfer cmdlet. This cmdlet is available in PowerShell versions 3.0 and later.
Here's an example of how to download a file using Start-BitsTransfer:
Start-BitsTransfer -Source "https://example.com/file.zip" -Destination "C:\Downloads\file.zip"
In this example, we're downloading the file "file.zip" from the URL "https://example.com/file.zip" and saving it to the "C:\Downloads" directory on our local computer. The Start-BitsTransfer cmdlet displays a progress bar while the file is being downloaded.
Downloading Files with Authentication
If the file you want to download is protected by a username and password, you can use the -Credential parameter when downloading the file. Here's an example of how to download a file with authentication:
$cred = Get-Credential
Invoke-WebRequest -Uri "https://example.com/file.zip" -OutFile "C:\Downloads\file.zip" -Credential $cred
In this example, we're using the Get-Credential cmdlet to prompt the user for their username and password. This
Resuming from where we left off, in the previous example, we stored the credentials in a variable named $cred, and then passed it to the Invoke-WebRequest cmdlet using the -Credential parameter. The cmdlet will then use these credentials to authenticate with the server and download the file.
Verifying File Integrity
After downloading a file, it's a good practice to verify its integrity to ensure that the file was not corrupted during the download process. One way to verify the file integrity is by using a checksum. A checksum is a unique string of characters generated from the file's content. By comparing the checksum of the downloaded file with the original checksum, you can determine if the file is intact.
Here's an example of how to verify the integrity of a downloaded file using a checksum:
$url = "https://example.com/file.zip"
$checksum = "ABCDEF0123456789"
Invoke-WebRequest -Uri $url -OutFile "C:\Downloads\file.zip"
$downloadedChecksum = (Get-FileHash "C:\Downloads\file.zip").Hash
if ($downloadedChecksum -eq $checksum) {
Write-Host "File integrity verified"
} else {
Write-Host "File corrupted"
}
In this example, we're downloading the file "file.zip" from the URL "https://example.com/file.zip" and saving it to the "C:\Downloads" directory on our local computer. After the download is complete, we use the Get-FileHash cmdlet to generate the checksum of the downloaded file and store it in the $downloadedChecksum variable. We then compare this value with the original checksum stored in the $checksum variable. If the values match, the file integrity is verified, and a message is displayed to the user.
Downloading Files with Resume Support
In some cases, the download process may be interrupted, and you may have to start the download process from the beginning. To avoid this, you can use the Start-BitsTransfer cmdlet, which supports resuming a download from where it was interrupted.
Here's an example of how to download a file with resume support:
Start-BitsTransfer -Source "https://example.com/file.zip" -Destination "C:\Downloads\file.zip" -Resume
In this example, we're downloading the file "file.zip" from the URL "https://example.com/file.zip" and saving it to the "C:\Downloads" directory on our local computer. The -Resume parameter is used to enable resume support, so if the download process is interrupted, you can resume the download from where it was left off.
In conclusion, downloading files in PowerShell is a straightforward process, and there are several options available for downloading single or multiple files, verifying file integrity, and downloading files with resume support. The examples provided in this article should give you a good starting point for working with file downloads in PowerShell.
Popular questions
Here are 5 questions and answers about downloading files in PowerShell:
- What is the most straightforward way to download a file in PowerShell?
The most straightforward way to download a file in PowerShell is by using the Invoke-WebRequest cmdlet. Here's an example:
Invoke-WebRequest -Uri "https://example.com/file.zip" -OutFile "C:\Downloads\file.zip"
In this example, the file "file.zip" is being downloaded from the URL "https://example.com/file.zip" and saved to the "C:\Downloads" directory on the local computer.
- How can you download a file that requires authentication in PowerShell?
To download a file that requires authentication in PowerShell, you can use the Invoke-WebRequest cmdlet and pass the credentials to the -Credential parameter. Here's an example:
$cred = Get-Credential
Invoke-WebRequest -Uri "https://example.com/file.zip" -OutFile "C:\Downloads\file.zip" -Credential $cred
In this example, the Get-Credential cmdlet is used to prompt the user for their credentials, which are then stored in the $cred variable. The Invoke-WebRequest cmdlet is then used to download the file, and the -Credential parameter is used to pass the stored credentials to the cmdlet.
- How can you verify the integrity of a downloaded file in PowerShell?
To verify the integrity of a downloaded file in PowerShell, you can use a checksum. A checksum is a unique string of characters generated from the file's content. By comparing the checksum of the downloaded file with the original checksum, you can determine if the file is intact. Here's an example:
$url = "https://example.com/file.zip"
$checksum = "ABCDEF0123456789"
Invoke-WebRequest -Uri $url -OutFile "C:\Downloads\file.zip"
$downloadedChecksum = (Get-FileHash "C:\Downloads\file.zip").Hash
if ($downloadedChecksum -eq $checksum) {
Write-Host "File integrity verified"
} else {
Write-Host "File corrupted"
}
In this example, the file is first downloaded using the Invoke-WebRequest cmdlet, and the Get-FileHash cmdlet is used to generate the checksum of the downloaded file. The original checksum is stored in the $checksum variable, and the two values are compared. If the values match, the file integrity is verified.
- Can you download files with resume support in PowerShell?
Yes, you can download files with resume support in PowerShell using the Start-BitsTransfer cmdlet. Here's an example:
Start-BitsTransfer -Source "https://example.com/file.zip" -Destination "C:\Downloads\file.zip" -Resume
In this example, the Start-BitsTransfer cmdlet is used to download the file "file.zip" from the URL "https://example.com/file.zip" and save it to the "C:\Downloads"
Tag
Downloading
