RegEx Procedure to find and define the RegEx.

Question

Hello,

I am looking for a solution how to create a regex. Are there any tools? Are there AI tools? I got this from Gego @gekka , works great. When I am given a new task, how do I find a solution, what can I do? Reason for this request.

Sample: What's happen when we get this?
Object0-EAN13CODE^PRODUCT=730180^Object1-TEXT^104612^Object2-TEXT^27730180^Object3-TEXT^AT1
Object0-EAN13CODE^PRODUCT=730181^Object1-TEXT^104612^Object2-TEXT^27730181^Object3-TEXT^AT1
// and I need to split it additional.
// OR
Object0-EAN13CODE^PROD730180^Object1-TEXT^104612^Object2-TEXT^27730180^Object3-TEXT^AT1
Object0-EAN13CODE^PROD730181^Object1-TEXT^104612^Object2-TEXT^27730181^Object3-TEXT^AT1
// and I have a prefix like this PROD
Input 
   1 to n entries like that
   
Object0-EAN13CODE^27730180^Object1-TEXT^104612^Object2-TEXT^27730180^Object3-TEXT^AT1
Object0-EAN13CODE^27730181^Object1-TEXT^104612^Object2-TEXT^27730181^Object3-TEXT^AT1
Object0-EAN13CODE^27730182^Object1-TEXT^104612^Object2-TEXT^27730182^Object3-TEXT^AT1
Object0-EAN13CODE^27730183^Object1-TEXT^104612^Object2-TEXT^27730183^Object3-TEXT^AT1
   
RegEx Object(?<NUM>\d+)-(?<KEY>.+?)\^(?<VALUE>.*?)\^
RegEx  (?<=(^|\^))Object(?<NUM>\d+)-(?<KEY>.+?)\^(?<VALUE>.*?)\^
       (?<=(^|\^))Object(?<NUM>\d+)-(?<KEY>.+?)\^(?<VALUE>.*?)\^
	   (?<=^|\^)Object(?<NUM>\d+)-(?<KEY>.+?)\^(?<VALUE>.*?)\^

How do I go about finding a solution?

 //  (?<=(^|\^))  what is it? Works too, without it.
 //  \d+ means match one or more digits.
 //  .+? form requires at least one character to match, while .*? can match none at all
 //  .*? matches any character (.) any number of times (*), as few times as possible to make the regex match (?).

How can I read out the group names and values specifically? See the picture.

 1
 	Key		Value
 	object0		type=DATAMATRIX value=27730180
 	object1		type=TEXT value=123419
 	object2		type=TEXT value=27730180
 	object3		type=TEXT value=AT1
 ------------
 2
 	Key		Value
 	object0		type=DATAMATRIX value=27730181
 	object1		type=TEXT value=123419
 	object2		type=TEXT value=27730181
 	object3		type=TEXT value=AT1
 ------------

Testtool

Answer 1

Hi @Markus Freitag , Welcome to Microsoft Q&A,

The (?<=(^|\^)) inside the regex pattern is a positive lookbehind assertion. It asserts that what precedes the current position in the string is either the start of the string ^ or a ^ character.

Now I would like to have a dictionary that contains the group names

string[] inputs ={
    "Object0-EAN13CODE^27730180^Object1-TEXT^104612^Object2-TEXT^27730180^Object3-TEXT^AT1^",
    "Object0-EAN13CODE^27730181^Object1-TEXT^104612^Object2-TEXT^27730181^Object3-TEXT^AT1^",
    "Object0-EAN13CODE^27730182^Object1-TEXT^104612^Object2-TEXT^27730182^Object3-TEXT^AT1^",
};

// Define a simpler regex pattern
Regex reg = new Regex(@"Object(?<NUM>\d+)-(?<KEY>.+?)\^(?<VALUE>.*?)\^");

var dictionaries = new List<Dictionary<int, object>>();

foreach (string input in inputs)
{
    // Match all key-value pairs in the input string
    MatchCollection matches = reg.Matches(input);

    // Create a dictionary to hold the key-value pairs for this input
    Dictionary<int, object> dict = new Dictionary<int, object>();

    // Iterate over each match and add it to the dictionary
    foreach (Match match in matches)
    {
        int num = int.Parse(match.Groups["NUM"].Value);
        string key = match.Groups["KEY"].Value;
        string value = match.Groups["VALUE"].Value;

        // Store key-value pairs in the dictionary
        dict[num] = new { type = key, value = value };
    }

    // Add the dictionary for this input to the list of dictionaries
    dictionaries.Add(dict);
}

// Output the dictionaries
for (int i = 0; i < dictionaries.Count; i++)
{
    Console.WriteLine($"Dictionary {i + 1}:");
    foreach (var kvp in dictionaries[i])
    {
        Console.WriteLine($"  Key: Object{kvp.Key}, Value: type={kvp.Value.GetType().GetProperty("type").GetValue(kvp.Value)}, value={kvp.Value.GetType().GetProperty("value").GetValue(kvp.Value)}");
    }
}

Best Regards,

Jiale

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