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

如果从Microsoft下载文件校验和完整性验证器(FCIV)，这将变成一行程序。

我从这里下载了FCIV: 文件校验和完整性验证工具的可用性和说明

执行如下命令。我有十份文件要检查。

Get-ChildItem WTAM*.tar | % {.\fciv $_.Name}

PowerShell One-Liners(字符串到散列)

MD5

([System.BitConverter]::ToString((New-Object -TypeName System.Security.Cryptography.MD5CryptoServiceProvider).ComputeHash((New-Object -TypeName System.Text.UTF8Encoding).GetBytes("Hello, World!")))).Replace("-","")

SHA1

([System.BitConverter]::ToString((New-Object -TypeName System.Security.Cryptography.SHA1CryptoServiceProvider).ComputeHash((New-Object -TypeName System.Text.UTF8Encoding).GetBytes("Hello, World!")))).Replace("-","")

SHA256

([System.BitConverter]::ToString((New-Object -TypeName System.Security.Cryptography.SHA256CryptoServiceProvider).ComputeHash((New-Object -TypeName System.Text.UTF8Encoding).GetBytes("Hello, World!")))).Replace("-","")

SHA384

([System.BitConverter]::ToString((New-Object -TypeName System.Security.Cryptography.SHA384CryptoServiceProvider).ComputeHash((New-Object -TypeName System.Text.UTF8Encoding).GetBytes("Hello, World!")))).Replace("-","")

SHA512

([System.BitConverter]::ToString((New-Object -TypeName System.Security.Cryptography.SHA512CryptoServiceProvider).ComputeHash((New-Object -TypeName System.Text.UTF8Encoding).GetBytes("Hello, World!")))).Replace("-","")

正如已接受的答案中所述，Get-FileHash很容易用于文件，但也可以用于字符串:

$s = "asdf"
Get-FileHash -InputStream ([System.IO.MemoryStream]::New([System.Text.Encoding]::ASCII.GetBytes($s)))

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()

这是我用来获得一致哈希值的方法:

function New-CrcTable {
    [uint32]$c = $null
    $crcTable = New-Object 'System.Uint32[]' 256

    for ($n = 0; $n -lt 256; $n++) {
        $c = [uint32]$n
        for ($k = 0; $k -lt 8; $k++) {
            if ($c -band 1) {
                $c = (0xEDB88320 -bxor ($c -shr 1))
            }
            else {
                $c = ($c -shr 1)
            }
        }
        $crcTable[$n] = $c
    }

    Write-Output $crcTable
}

function Update-Crc ([uint32]$crc, [byte[]]$buffer, [int]$length, $crcTable) {
    [uint32]$c = $crc

    for ($n = 0; $n -lt $length; $n++) {
        $c = ($crcTable[($c -bxor $buffer[$n]) -band 0xFF]) -bxor ($c -shr 8)
    }

    Write-Output $c
}

function Get-CRC32 {
    <#
        .SYNOPSIS
            Calculate CRC.
        .DESCRIPTION
            This function calculates the CRC of the input data using the CRC32 algorithm.
        .EXAMPLE
            Get-CRC32 $data
        .EXAMPLE
            $data | Get-CRC32
        .NOTES
            C to PowerShell conversion based on code in https://www.w3.org/TR/PNG/#D-CRCAppendix

            Author: Øyvind Kallstad
            Date: 06.02.2017
            Version: 1.0
        .INPUTS
            byte[]
        .OUTPUTS
            uint32
        .LINK
            https://communary.net/
        .LINK
            https://www.w3.org/TR/PNG/#D-CRCAppendix

    #>
    [CmdletBinding()]
    param (
        # Array of Bytes to use for CRC calculation
        [Parameter(Position = 0, ValueFromPipeline = $true)]
        [ValidateNotNullOrEmpty()]
        [byte[]]$InputObject
    )

    $dataArray = @()
    $crcTable = New-CrcTable
    foreach ($item  in $InputObject) {
        $dataArray += $item
    }
    $inputLength = $dataArray.Length
    Write-Output ((Update-Crc -crc 0xffffffffL -buffer $dataArray -length $inputLength -crcTable $crcTable) -bxor 0xffffffffL)
}

function GetHash() {
    [CmdletBinding()]
    param(
        [Parameter(Position = 0, ValueFromPipeline = $true)]
        [ValidateNotNullOrEmpty()]
        [string]$InputString
    )

    $bytes = [System.Text.Encoding]::UTF8.GetBytes($InputString)
    $hasCode = Get-CRC32 $bytes
    $hex = "{0:x}" -f $hasCode
    return $hex
}

function Get-FolderHash {
    [CmdletBinding()]
    param(
        [Parameter(Position = 0, ValueFromPipeline = $true)]
        [ValidateNotNullOrEmpty()]
        [string]$FolderPath
    )

    $FolderContent = New-Object System.Collections.ArrayList
    Get-ChildItem $FolderPath -Recurse | Where-Object {
        if ([System.IO.File]::Exists($_)) {
            $FolderContent.AddRange([System.IO.File]::ReadAllBytes($_)) | Out-Null
        }
    }

    $hasCode = Get-CRC32 $FolderContent
    $hex = "{0:x}" -f $hasCode
    return $hex.Substring(0, 8).ToLower()
}