Compare two CSV file (Text File) data in ASP.Net

Here I have created sample that will help you out.

C#

protected void Page_Load(object sender, EventArgs e)
{
    bool IsMatchedFirstColumn = GetCSVDiff(Server.MapPath("CSVs/1.csv"), Server.MapPath("CSVs/2.csv"), 1);
    bool IsMatchedSecondColumn = GetCSVDiff(Server.MapPath("CSVs/1.csv"), Server.MapPath("CSVs/2.csv"), 2);
}

private bool GetCSVDiff(string firstFile, string secondFile, int columnIndex)
{
    bool isColumnMatched = true;
    columnIndex = columnIndex - 1;
    int i = 0;
    foreach (var fileoneline in File.ReadAllLines(firstFile))
    {
        int j = 0;
        foreach (var line in File.ReadAllLines(secondFile))
        {
            if (i == j)
            {
                var fields = line.Split(new char[] { ';' }, 2);
                if (fileoneline.Split(';')[0].Split(',')[columnIndex].Trim() != fields[0].Split(',')[columnIndex].Trim())
                {
                    isColumnMatched = false;
                    break;
                }
            }
            j++;
        }
        i++;
    }
    return isColumnMatched;
}

1.csv

1,2,3,4

2,2,3,4

2.csv

1,2,3,4

2,3,3,4

Screenshot