powershell - Convert fixed width txt file to CSV / set-content or out-file -append?

Question

Input file is a fixed-width txt file. My client normally opens it in Excel and manually specifies the column breaks. I'm hoping to replace certain blank spaces with a comma, so that I can parse as CSV and save as XLS or whatever.

$columBreaks = 20, 35, 50, 80, 100, 111, 131, 158, 161, 167, 183
[array]::Reverse($columBreaks) #too lazy to re-write array after finding out I need to iterate in reverse

$files = get-childitem ./ |where-object {$_.Name -like "FileFormat*.txt"}

foreach($file in $files)
{
    $name = $file.Name.split(".")
    $csvFile = $name[0]+".csv"
    if (!(get-childitem ./ |where-object {$_.Name -like $csvFile})) #check whether file has been processed
    { 
        $text = (gc $file) 
        foreach ($line in $text)
        {
           foreach ($pos in $columBreaks)
            {
                #$line.Substring($char-1,3).replace(" ", ",")
                $line = $line.Insert($pos,",")
                #out-file -append?
            }
        } 
    }
    #set-content?
}

So what's the most efficient way to write this content out? I had hoped to use set-content, but I don't think that's possible since we're processing line by line, so I think I would either have to build an array of lines for set-content, or use write-out -append for each iteration. Is there a more efficient way to do this?

Answer 1

Set-Content should work fine with some minor adjustments. Here is an example of how it should work (this is everything within your outer foreach loop):

$csvFile = $file.BaseName
    if (!(get-childitem ./ |where-object {$_.Name -like $csvFile})) #check whether file has been processed
    { 
        (gc $file | foreach {
                $_.Insert($columBreaks[0],",").Insert($columBreaks[1],",").Insert($columBreaks[2],",").`
                Insert($columBreaks[3],",").Insert($columBreaks[4],",").Insert($columBreaks[5],",").`
                Insert($columBreaks[6],",").Insert($columBreaks[7],",").Insert($columBreaks[8],",").`
                Insert($columBreaks[9],",").Insert($columBreaks[10],",")
            }) | set-content $csvFile #note parenthesis around everything that gets piped to set-content
    }

By the way, instead of splitting the filename on the '.', you can just get the name without the extension by using $file.BaseName:

$csvFile = $file.BaseName + ".csv"