CODEWITHSUNDEEP
c#regexstringlinq
user1260827
user1260827

Reputation: 1520

substring value from string

I have a string variable that contain [l=9;f=0;r=5;p=2]. There are may be a more than one:[l=9;f=0;r=5;p=2],[l=9;f=0;r=6;p=2].

I want to get List of Tuple<int,int,int>, where item1 = value of l, item2= value of r, item3=value of p. What is best approach to do this?
My code:

  // split string
    var splittedFormatedSeats = Regex.Matches(formatSeats, @"\[.+?\]")
                            .Cast<Match>()
                            .Select(m => m.Value)
                            .ToList();


     IList<Tuple<int,int,int>> fullSeat = new List<Tuple<int, int, int>>();
       foreach (var splittedFormatedSeat in splittedFormatedSeats)
       {

          ...
       }

Thanks.

Upvotes: 2

Views: 399

Answers (3)

Steve B
Steve B

Reputation: 37710

I would adopt another strategy. First, split subcomponents of your string

var components = formatSeats.Split(',');

This will give you an array of string. This will be far more efficient to parse small chunks of strings instead of a big string.

You can then use either a Regex to extract the values or a simple code like this :

foreach(var component in components)
{
    var parts = component.Trim("[]".ToCharArray()).Split(';');

}

var results = from component in components
              let c = component.Trim("[]".ToCharArray())
                               .Split(';')
                               .Select(c=>int.Parse(c.SubString(2))
              select new { l = c[0], f=c[1], r=c[2], p = c[3] };

This will produces an enumeration of an anonymous type.

foreach(var x in results)
{
    Console.WriteLine("{0} / {1} / {2} / {3}", x.l, x.f, x.r, x.p);
}

If you actually need a Tuple simply change the code to :

var results = from component in components
              let c = component.Trim("[]".ToCharArray())
                               .Split(';')
                               .Select(c=>int.Parse(c.SubString(2))
              select new Tuple<int,int,int,int>{ l = c[0], f=c[1], r=c[2], p = c[3] };

I would however, advocate for writing a small struct to simplify the code and raise its readability.

public struct MyValue
{
     private readonly int m_L; 
     public int L { get {return m_L; } }

     private readonly int m_F; 
     public int F { get {return m_F; } }

     private readonly int m_R; 
     public int R { get {return m_R; } }

     private readonly int m_P; 
     public int P { get {return m_P; } }

     public MyValue(int l, int f, int r, int p)
     {
         m_L = l;
         m_F = f;
         m_R = r;
         m_P = p;
     }
}
....


var results = from component in components
          let c = component.Trim("[]".ToCharArray())
                           .Split(';')
                           .Select(c=>int.Parse(c.SubString(2))
          select new MyValue(c[0],c[1],c[2],c[3]);

Finally, if the string always have this form, you could avoid using the Regex.

Upvotes: 3

Vignesh.N
Vignesh.N

Reputation: 2666

        string formattedString = "[l=9;f=0;r=5;p=2],[l=9;f=0;r=6;p=2]";
        var splitString = formattedString.Split(',')
                                    .Select(p => p.Trim(new char[]{'[',']',' '}));

        List<Tuple<int, int, int, int>> tupleList = new List<Tuple<int, int, int, int>>();
        foreach (var item in splitString)
        {
            int[] finalSplit = item.Split(';').Select(p => 
                                                      Convert.ToInt32(p.Substring(p.LastIndexOf('=')+1).Trim())
                                                      ).ToArray();
            tupleList.Add(new Tuple<int, int, int, int>(finalSplit[0], finalSplit[1],
                                    finalSplit[2], finalSplit[3]));
        }

This will split values of l, f, r and p and add them to the Tuple.

Upvotes: 2

Eoin Campbell
Eoin Campbell

Reputation: 44306

Is the format of your inner string always the same ? Is it always a single digit value for each variable (l, f, r & p)?

If so you can just substring them out.

foreach(var splittedFormatedSeat  in splittedFormatedSeats)
{
    int x, y, z;
    string s = splittedFormatedSeat .ToString();
    if(int.TryParse(s[3].ToString(), out x) &&
       int.TryParse(s[11].ToString(), out y) &&
       int.TryParse(s[15].ToString(), out z))
       fullSeat.Add(new Tuple<int,int,int>(x,y,z));
}

Upvotes: 1

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