How to read file that contains one row with multiple records- C#

Question

I have this text file that only has one row. Each file contains one customer name but multiple items and descriptions.
Record starting with 00 (Company Name) has a char length of 10
01 (Item#) - char length of 10
02 (Description) - char length of 50

I know how to read a file, but I don't have any idea of how to loop through only one line, find records 00, 01, 02 and grab the text based on the length, finally start at the position of the last records and start the loop again. Can someone please give me an idea of how to read files like this?

output:

companyName     16622        Description
companyName     15522        Description

input text file example

00Init    0115522   02Description                                     0116622   02Description                                    

Answer 1

This solution assumes that the data is fixed width, and that item number will preceed description (01 before 02). This solution will emit a record every time a description record is encountered, and deals with multiple products for the same company.

First, define a class to hold your data:

public class Record
{
    public string CompanyName { get; set; }
    public string ItemNumber { get; set; }
    public string Description { get; set; }
}

Then, iterate through your string, returning a record when you've got a description:

public static IEnumerable<Record> ReadFile(string input)
{
    // Alter these as appropriate
    const int RECORDTYPELENGTH = 2;
    const int COMPANYNAMELENGTH = 41;
    const int ITEMNUMBERLENGTH = 8;
    const int DESCRIPTIONLENGTH = 48;

    int index = 0;
    string companyName = null;
    string itemNumber = null;

    while (index < input.Length)
    {
        string recordType = input.Substring(index, RECORDTYPELENGTH);
        index += RECORDTYPELENGTH;

        if (recordType == "00")
        {
            companyName = input.Substring(index, COMPANYNAMELENGTH).Trim();
            index += COMPANYNAMELENGTH;
        }
        else if (recordType == "01")
        {
            itemNumber = input.Substring(index, ITEMNUMBERLENGTH).Trim();
            index += ITEMNUMBERLENGTH;
        }
        else if (recordType == "02")
        {
            string description = input.Substring(index, DESCRIPTIONLENGTH).Trim();
            index += DESCRIPTIONLENGTH;

            yield return new Record
            {
                CompanyName = companyName,
                ItemNumber = itemNumber,
                Description = description
            };
        }
        else 
        {
            throw new FormatException("Unexpected record type " + recordType);
        }
    }
}

Note that your field lengths in the question don't match the sample data, so I adjusted them so that the solution worked with the data you provided. You can adjust the field lengths by adjusting the constants.

Use this like the following:

string input = "00CompanyName                              0115522   02Description                                     0116622   02Description                                     ";

foreach (var record in ReadFile(input))
{
    Console.WriteLine("{0}\t{1}\t{2}", record.CompanyName, record.ItemNumber, record.Description);
}