(
    [System.Security.Cryptography.MD5CryptoServiceProvider]::new().ComputeHash(
        [System.Text.UTF8Encoding]::new().GetBytes($yourText)
    ) `
    | %{ [Convert]::ToString($_, 16) }
) -join ''

$yourText = 'hello'输出5d41402abc4b2a76b9719d911017c592

这个网站有一个例子:使用Powershell进行MD5校验和。它使用. net框架实例化MD5哈希算法的实例来计算哈希值。

下面是本文的代码，包含Stephen的注释:

param
(
  $file
)

$algo = [System.Security.Cryptography.HashAlgorithm]::Create("MD5")
$stream = New-Object System.IO.FileStream($Path, [System.IO.FileMode]::Open,
    [System.IO.FileAccess]::Read)

$md5StringBuilder = New-Object System.Text.StringBuilder
$algo.ComputeHash($stream) | % { [void] $md5StringBuilder.Append($_.ToString("x2")) }
$md5StringBuilder.ToString()

$stream.Dispose()

从PowerShell版本4开始，使用Get-FileHash cmdlet可以很容易地实现文件的开箱即用:

Get-FileHash <filepath> -Algorithm MD5

这当然是更可取的，因为它避免了注释中指出的旧PowerShell解决方案所提供的问题(使用流，关闭它，并支持大文件)。

如果内容是字符串:

$someString = "Hello, World!"
$md5 = New-Object -TypeName System.Security.Cryptography.MD5CryptoServiceProvider
$utf8 = New-Object -TypeName System.Text.UTF8Encoding
$hash = [System.BitConverter]::ToString($md5.ComputeHash($utf8.GetBytes($someString)))

对于较旧的PowerShell版本

如果内容为文件:

$someFilePath = "C:\foo.txt"
$md5 = New-Object -TypeName System.Security.Cryptography.MD5CryptoServiceProvider
$hash = [System.BitConverter]::ToString($md5.ComputeHash([System.IO.File]::ReadAllBytes($someFilePath)))

这里有两行，只需在第2行中更改“hello”:

PS C:\> [Reflection.Assembly]::LoadWithPartialName("System.Web")
PS C:\> [System.Web.Security.FormsAuthentication]::HashPasswordForStoringInConfigFile("hello", "MD5")

如果你正在使用PowerShell社区扩展，有一个Get-Hash命令可以很容易地做到这一点:

C:\PS> "hello world" | Get-Hash -Algorithm MD5


Algorithm: MD5


Path       :
HashString : E42B054623B3799CB71F0883900F2764

团队! 看看我的哈希计算函数。

Function Get-StringHash {
<#
    .DESCRIPTION
        Get string persistant hash.        
#>
    [OutputType([string])]
    [CmdletBinding()]
    Param(
        [Parameter( Mandatory = $True, Position = 0, HelpMessage = "String to calculate hash." )]
        [string] $String,
        [Parameter( Mandatory = $false, Position = 0, HelpMessage = "String encoding." )]
        [ValidateSet( 'UTF8' )]
        [string] $StringEncoding = 'UTF8',
        [Parameter( Mandatory = $false, Position = 2, HelpMessage = "Hash algoritm." )]
        [ValidateSet( 'md5', 'sha256', 'sha512' )]
        [string] $Algoritm = 'sha256'
    )
    try {
        #region functions
        #endregion

        $Result = $null

        switch ( $Algoritm ) {
            'md5' {  
                $HashProvider = New-Object -TypeName System.Security.Cryptography.MD5CryptoServiceProvider
            }
            'sha256' {  
                $HashProvider = New-Object -TypeName System.Security.Cryptography.SHA256CryptoServiceProvider
            }
            'sha512' {  
                $HashProvider = New-Object -TypeName System.Security.Cryptography.SHA512CryptoServiceProvider
            }
            Default {}
        }

        switch ( $StringEncoding ) {
            'UTF8' {  
                $Encoding = New-Object -TypeName System.Text.UTF8Encoding
            }
            Default {}
        }
        
        
        $Result = [System.BitConverter]::ToString( $HashProvider.ComputeHash( $Encoding.GetBytes( $String ) )).replace('-','')

    }
    catch {
        Get-ErrorReporting -Trap $_
    }

    return $Result
}

$String   = 'Some text'
$Algoritm = 'MD5'

$Hash = Get-StringHash -String $String -Algoritm $Algoritm

write-host "$String has $Algoritm hash $hash"