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How to separate a string into codepoint-wise characters with PowerShell


You have a Unicode string that contain non-ASCII characters as well as ASCII characters. You want to separate that string into characters.


If you split the string with the code below:

$TemporaryArray = $InputString -split "";
$ResultArray = $TemporaryArray[1..($TemporaryArray.length-2)];

You will have a problem: characters that represented as surrogate pair (U+10000 ~ U+10FFFF) will separated high surrogate and low surrogate (they are not character).


PowerShell -split operator is not surrogate pair aware, and it seems by design.


Once convert the string into UTF32 byte-array, and separate it into codepoints (4-byte length), and convert them to String object.

$ResultArray = @();
$InputStringBytes = [Text.Encoding]::UTF32.GetBytes($InputString);
for ($i=0; $i -lt $InputStringBytes.length; $i+=4) {
     $ResultArray += [Text.Encoding]::UTF32.GetString($InputStringBytes, $i, 4);


This method separate a string into each codepoint, so the Unicode ligatures (it consists of two or more codepoints) are illegally separated into codepoints. You can use for this purpose.