用空格替换前导零

Question

I have a text file of multiple records. Each record has a field which has some number of leading zeros that I need to replace with that number of spaces. A record will look like this:

A206   000001204   X4609

I need the record to look like this:

A206        1204   X4609

I'm extremely unfamiliar with regex but the following regex seems to find the matches that I need:

\b0+

However, I have no idea how to do the replacement. A ReplaceAll for Notepad++ would be awesome but I can also create a quick program in C#, Powershell, or Python if needed. Can anyone give me some pointers on the regex for this?

Answer 1

Yes, \\b0+ would probably work.

Here using the Regex.Replace() method in C# :

using System.Text.RegularExpressions;

Regex.Replace(inputString, @"\b0+", m => "".PadLeft(m.Value.Length,' '));

The last argument to Replace() is a simple lambda function that returns a string of the same length as the number of matched 0 s, but consisting only of spaces

---

You can do the same in PowerShell , substituting a scriptblock for the lambda function:

PS C:\> $inputString = 'A206   000001204   X4609'
PS C:\> [regex]::Replace($inputString, '\b0+', {param($m) ' ' * $m.Value.Length})
A206        1204   X4609

Answer 2

Does this suffice?

while (dataString.Contains(" 0")) // while data contains a zero after a space
    dataString = dataString.Replace(" 0", "  "); // Replace with two spaces

Though this doesn't use regex.

I hope this helps.

Answer 3

Using Npp:

• Ctrl + H
• Find what: \\b0
• Replace with: (a space)
• Replace All

Answer 4

As an alternative to Mathias' lambda expression solution you could also use a more "conventional" approach like this:

$str = 'A206   000001204   X4609'
$re  = '\b0+'

if ($str -match $re) {
  $str -replace $re, (' ' * $matches[0].Length)
}

Answer 5

My Notepad++ regex suggestion is not as short as Toto's, but it is a little more strict.

Find what: (?: \\K|\\G)0

Replace with:

This will seek out a space, then forget it (compliments of \\K -- the Keep metacharacter), then individually match each consecutive zero (compliments of \\G -- the Continue metacharacter).

Replace All will deliver the desired result.

I am posting this to make this page a little more accommodating for future researchers who may have slightly different requirements.