How to split CSV file

You can do it via the following way..

using System.IO;
static void Main(string[] args)
{
    using(var reader = new StreamReader(@"C:\test.csv"))
    {
        List<string> listA = new List<string>();
        List<string> listB = new List<string>();
        while (!reader.EndOfStream)
        {
            var line = reader.ReadLine();
            var values = line.Split(','); // or whatever yur get by reading that file

            listA.Add(values[0]);
            listB.Add(values[1]);
        }
    }
}

A CSV file is either a Tab delimited or a Comma delimited file. That said; you have to read the file line by line and then separate the values available in a line based on the delimiter character. The first line usually appears in a CSV file is usually the headers which you can use in order to produce a KeyValue pair to make your collection more efficient. For example:

 Dictionary<int, Dictionary<String, String>> values = new Dictionary<int, Dictionary<String,String>>();
 using(FileStream fileStream = new FileStream(@"D:\MyCSV.csv", FileMode.Open, FileAccess.Read, FileShare.Read)) {
     using(StreamReader streamReader = new StreamReader(fileStream)){
          //You can skip this line if there is no header
          // Then instead of Dictionary<String,String> you use List<String>
          var headers = streamReader.ReadLine().Split(',');
          String line = null;
          int lineNumber = 1;
          while(!streamReader.EndOfStream){
               line = streamReader.ReadLine().split(',');
               if(line.Length == headers.Length){
                   var temp = new Dictionary<String, String>();
                   for(int i = 0; i < headers.Length; i++){
                      // You can remove '"' character by line[i].Replace("\"", "") or through using the Substring method
                      temp.Add(headers[i], line[i]);
                   }
                   values.Add(lineNumber, temp);
               }
               lineNumber++;
          }              
     }

In case the data structure of your CSV is constant and it will not change in the future, you can develop a strongly typed data model and get rid of the Dictionary type. This approach will be more elegant and more efficient.

First of all, your CSV lines are surrounded by quotes. Is it copy/paste mistake? If not, you will need to sanitize the file to a valid CSV file.

You can try Cinchoo ETL - an open source library to load the CSV file to datatable, then you can assign it to your DataGridView source.

I'll show you both approach, how to handle

Valid CSV: (test.csv)

0.0.0.0,"0.255.255.255","ZZ"
1.0.0.0,"1.0.0.255","AU"
1.0.1.0,"1.0.3.255","CN"
1.0.4.0,"1.0.7.255","AU"
1.0.8.0,"1.0.15.255","CN"
1.0.16.0,"1.0.31.255","JP"
1.0.32.0,"1.0.63.255","CN"
1.0.64.0,"1.0.127.255","JP"
1.0.128.0,"1.0.255.255","TH"
1.1.0.0,"1.1.0.255","CN"
1.1.1.0,"1.1.1.255","AU"
1.1.2.0,"1.1.63.255","CN"
1.1.64.0,"1.1.127.255","JP"
1.1.128.0,"1.1.255.255","TH"

Read CSV:

using (var p = new ChoCSVReader("test.csv"))
{
    var dt = p.AsDataTable();
    //Assign dt to DataGridView
}

Next approach

Invalid CSV: (test.csv)

"0.0.0.0,""0.255.255.255"",""ZZ"""
"1.0.0.0,""1.0.0.255"",""AU"""
"1.0.1.0,""1.0.3.255"",""CN"""
"1.0.4.0,""1.0.7.255"",""AU"""
"1.0.8.0,""1.0.15.255"",""CN"""
"1.0.16.0,""1.0.31.255"",""JP"""
"1.0.32.0,""1.0.63.255"",""CN"""
"1.0.64.0,""1.0.127.255"",""JP"""
"1.0.128.0,""1.0.255.255"",""TH"""
"1.1.0.0,""1.1.0.255"",""CN"""
"1.1.1.0,""1.1.1.255"",""AU"""
"1.1.2.0,""1.1.63.255"",""CN"""
"1.1.64.0,""1.1.127.255"",""JP"""
"1.1.128.0,""1.1.255.255"",""TH"""

Read CSV:

using (var p = new ChoCSVReader("Sample6.csv"))
{
    p.SanitizeLine += (o, e) =>
    {
        string line = e.Line as string;
        if (line != null)
        {
            line = line.Substring(1, line.Length - 2);
            line = line.Replace(@"""""", @"""");
        }

        e.Line - line;
    };

    var dt = p.AsDataTable();
    //Assign dt to DataGridView
}

Hope it helps.