built-in reverse

文字列の反転
文字列の反転 PowerShellにて 
function ReverseString([string] $String) {
    $charArray = $String.ToCharArray()
    [Array]::Reverse($charArray)
    -join $charArray
}

First, we turn the string into an array of chars. Then, we pass the char array into the static method Reverse of the class Array from .NET. Finally, we use -join to concatenate this char array back into one single string.

Array.Reverse method.

2026年09月23日(水) · 役に立ちましたか？

PowerShellの文字列の反転に対する他のアプローチ

コミュニティがこの演習を解いた他の方法
function ReverseString([string] $String) {
    -join $String[$String.Length..0]
}
join range operator

Reverse the string using foreach loop. 

function ReverseString([string] $String) {
    $strBuilder = [System.Text.StringBuilder]::new()
    foreach ($i in ($String.Length - 1)..0) {
        [void] $strBuilder.Append($String[$i])
    }
    $strBuilder.ToString()
}
string builder

Build a new string using string builder. 

function ReverseString([char[]] $String) {
    $last = $String.Count - 1
    $mid  = [Math]::Ceiling($String.Count / 2)
    for ($i = 0; $i -lt $mid; $i++) {
        $String[$i], $String[$last - $i] = $String[$last - $i], $String[$i]
    }
    -join $String
}
reverse in place

Reverse the char array in place.