更适合Powershell体质的ln

前言

在更适合Powershell体质的grep中重定义了grep。Linux中的ln命令也非常好用，创建软链接，可以省下很多需要复用的文件空间。

没想到Powershell中没办法使用cmd的mklink，自带的创建软连接命令比我命还长。自己写一个脚本重定向！

代码

因为不能执行cmd命令，只能使用Powershell函数，因此新建一个ln.psm1模块，并保存到C:\Users\UserName\Documents\PowerShell\Modules\ln，在Powershell初始化时导入即可。

function ln {

    param(
        [switch]$d,      # -d: 强制目录链接
        [switch]$h,      # -h: 显示帮助
        [string]$target,
        [string]$link
    )

    # ======== 彩色帮助 ========
    if ($h -or -not $target -or -not $link) {

        Write-Host ""  # 空行

        Write-Host "ln: create symbolic link " -ForegroundColor Cyan -NoNewline
        Write-Host "(PowerShell version)" -ForegroundColor DarkGray

        Write-Host ""
        Write-Host "Usage:" -ForegroundColor Yellow
        Write-Host "  ln [-d] <target> <link>" -ForegroundColor White

        Write-Host ""
        Write-Host "Options:" -ForegroundColor Yellow
        Write-Host "  -d        create directory symbolic link" -ForegroundColor White
        Write-Host "  -h        display this help" -ForegroundColor White

        Write-Host ""
        Write-Host "Examples:" -ForegroundColor Yellow
        Write-Host "  ln C:\real\file.txt C:\link\file.txt" -ForegroundColor Green
        Write-Host "  ln C:\realDir C:\linkDir" -ForegroundColor Green
        Write-Host "  ln -d C:\realDir C:\linkDir" -ForegroundColor Green

        Write-Host ""
        return
    }

    # ======== 参数检查 ========
    if (-not (Test-Path $target)) {
        Write-Host "ln: target '$target' not found" -ForegroundColor Red
        return
    }

    # ======== 设置类型（SymbolicLink）========
    $itemType = "SymbolicLink"

    # ======== 创建符号链接 ========
    try {
        New-Item -ItemType $itemType -Path $link -Target $target | Out-Null
        Write-Host "ln: created symbolic link " -ForegroundColor Cyan -NoNewline
        Write-Host "'$link'" -ForegroundColor Green -NoNewline
        Write-Host " → " -ForegroundColor DarkGray -NoNewline
        Write-Host "'$target'" -ForegroundColor Green
    }
    catch {
        Write-Host "ln: failed to create link: $($_.Exception.Message)" -ForegroundColor Red
    }
}