Looping thorugh selective SharePoint List columns

Question

I have a share-point list called "Employees". I have the following columns:

• Title
• FirstName
• LastName
• Band1
• Band2
• Band3
• Band4

I have 20 band columns, but I have only included 4 band columns in order to better explain the problem. I know how to get data from specific columns, but how do I go about doing the following:

1. Get total number of "Band" columns only from the list above
2. Loop through each "Band" column and get/display the items/values in each of the bands

My first though it to have a loop that loops through all the band columns, then have a loop inside that to get/display each item/value inside of each band but I am not entirely sure how to go about it doing it

Any ideas or suggestion would greatly appreciated,

Thanks,

Answer 1

To get all the Band fields, I'd do something like

var fieldLookup = mySpList.Fields.Cast<SPField>()
    .Where(f => f.Title.StartsWith("Band"))
    .Select(f => { 
            int bandNo;
            bool successful = int.TryParse(f.Title.Substring(4), out bandNo);
            return new { Id = f.Id, BandNo = bandNo, Success = successful };
        })
    .Where(a => a.Success)
    .ToDictionary(a => a.BandNo, a => a.Id);

This should get you a Dictionary<int, Guid> that maps the band number from the column heading to the ID of the field.

You can then use these IDs to fetch the values. For example, you can build a list of <FieldRef> elements to pass into an SPQuery, or you can just do

foreach (SPListItem item in myList.Items)
{
    Console.WriteLine("Item {0}", item.Title);
    foreach(int bandNo in fieldLookup.Keys)
    {
        Console.WriteLine("Band {0}: {1}", bandNo, item[fieldLookup[bandNo]]);
    }
}