I want to replace the dash(-) to space from a string at position 12. I cannot use replace("-"," ") because there may a negative number in the string.

I had try (?<=^(?:.{11})). but it only get the result at first line.

Are there any solution?

 K120613763-01       1100625     TL             -11,008                 0           -11,008                                                                                        
 N123203270-02       1101024     PWL               -387                 0              -387                                                                                        
 I200543078-01       1101029     PDDW              -311                 0              -311                                                                                        
 A122285277-03       1101101     PWL                530                 0               530                                                                                      
 A127477426-03       1101101     PWL                458                 0               458                                                                                      

I want the result like below.

 K120613763 01       1100625     TL             -11,008                 0           -11,008                                                                                        
 N123203270 02       1101024     PWL               -387                 0              -387                                                                                        
 I200543078 01       1101029     PDDW              -311                 0              -311                                                                                        
 A122285277 03       1101101     PWL                530                 0               530                                                                                      
 A127477426 03       1101101     PWL                458                 0               458                                                                                      

Note: Lines start with a space

I use vb.net to programming in uipath.

I tried this but it doesn't work:

System.Text.RegularExpressions.Regex.Replace(strTxt, "/(?<=^(?:.{11}))./gm"," ")

CodePudding user response：

You can match a hyphen after 11 characters and use a multiline notation like

System.Text.RegularExpressions.Regex.Replace(strTxt, "(?m)(?<=^.{11})-"," ")

CodePudding user response：

It's all flavor dependent, but usally ^ will me mean start of input, Use the multiline modier /re/m:

/(?<=^(?:.{11}))./m

and a replace function sometimes only replaces the first occasion of the pattern use the global modifer as well: /re/g:

/(?<=^(?:.{11}))./gm

CodePudding user response：

Use a negative look behind to match the 12th character:

(?<=^.{11}).

(see live demo)

And replace it with a -

You'll need to use the "global" option when doing the replace.

CodePudding user response：

/(?<=^\s\S{10})-(?=.*$)/gmi

Explanation

• Positive Lookbehind (?<=^\s\S{10}) Assert that the Regex below matches:
  • ^ asserts position at start of a line
  • \s matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
  • \S matches any non-whitespace character (equivalent to [^\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
  • {10} matches the previous token exactly 10 time
• - matches the character - with index 45₁₀ (2D₁₆ or 55₈) literally (case insensitive)
• Positive Lookahead (?=.*$) Assert that the Regex below matches:
  • . matches any character (except for line terminators)
  • * matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
  • $ asserts position at the end of a line
• Global pattern flags
  • g modifier: global. All matches (don't return after first match)
  • m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
  • i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])

A working example can be found here: https://dotnetfiddle.net/cLZeka

using System;
using System.Text.RegularExpressions;

public class Example
{
    public static void Main()
    {
        string pattern = @"(?<=^\s\S{10})-(?=.*$)";
        string substitution = @" ";
        string input = @" K120613763-01       1100625     TL             -11,008                 0           -11,008                                                                                        
 N123203270-02       1101024     PWL               -387                 0              -387                                                                                        
 I200543078-01       1101029     PDDW              -311                 0              -311                                                                                        
 A122285277-03       1101101     PWL                530                 0               530                                                                                      
 A127477426-03       1101101     PWL                458                 0               458                                                                                      ";
        RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase;
        
        Regex regex = new Regex(pattern, options);
        string result = regex.Replace(input, substitution);
    }
}