Last week I posted a PowerShell snippet on Twitter. My original post piped an array of integers as [CHAR] type using an OFS. Don't worry about that. As many people reminded me, it is much easier to use the -Join operator.<\/p>\n
-join [char[]](116,103,105,102)<\/pre>\nI'll let you try that on your own. The [CHAR] type is used to represent a character as an integer value, like this:<\/p>\n
PS C:\\> [char]120\r\nx<\/pre>\nFor this week's Friday Fun I thought it would be nice to translate a string of text into corresponding character values. It looks like a secret code! Or we could use the translation in a join scriptblock. So I put together a little script I call Translate-ToChar.ps1. The script takes a string of text and writes an array of [CHAR] objects.<\/span><\/p>\n
Param(\r\n[Parameter(Position=0)]\r\n[ValidateNotNullOrEmpty()]\r\n[string]$Text=\"PowerShell Rocks!\",\r\n[switch]$Scriptblock\r\n)\r\n\r\n#create CHAR mapping hash table\r\n$map=@{}\r\n33..125 | foreach { $map.Add([string]$_,[char]$_)}\r\n\r\n#create an empty array to hold the CHAR values\r\n$values=@()\r\n$text.ToCharArray() | foreach {\r\n#because $_ will change, save the current piped in character as a variable\r\n$ltr=$_\r\n[int]$i=($map.getEnumerator() | where {$_.value -ceq $ltr }).Name\r\n#add the value to the array\r\n$values+=$i\r\n}\r\n\r\nif ($ScriptBlock) {\r\n#write a scriptblock to the pipeline\r\n#create the command\r\n$ofs=\",\"\r\n#create a variable so we variable expansion of $values\r\n$t=\"-join [char[]]($values)\"\r\n\r\n#put it back together as a script block and write to the pipeline\r\n[scriptblock]::Create($t)\r\n}\r\nelse {\r\n#write value array\r\n$values\r\n}<\/pre>\nThe script begins by defining a map hash table for what I think are all characters you are likely to find on a US keyboard. These should be character values 33 through 125 which I get using the range (..) operator.<\/p>\n
$map=@{}\r\n33..125 | foreach { $map.Add([string]$_,[char]$_)}<\/pre>\nEach number is piped to ForEach object where I add it to the hash table. In order to get the hash table key to work properly I cast the number as a string and the hash table value is the same number cast as a [CHAR]. Now we can begin breaking the string apart and \"translating\" it.<\/p>\n
$text.ToCharArray() | foreach {\r\n#because $_ will change, save the current piped in character as a variable\r\n$ltr=$_<\/pre>\nThe script splits the string into a character array using the default delimiter of a space. Because I'm going to be using a pipelined expression, I save the current letter as a variable. It will keep things straight in a moment.<\/p>\n
The next step is to find the character in the hash table values. I found the best way to accomplish this was to call the hash table's GetEnumerator() method. This way I can pipe it to Where-Object and find the corresponding key.<\/p>\n
[int]$i=($map.getEnumerator() | where {$_.value -ceq $ltr }).Name\r\n#add the value to the array\r\n$values+=$i<\/pre>\n