I have a dataset that I need to filter on multiple columns (six in total). Not every column will be filtered, i.e. a user can filter on column 1 and 3, but not 2,4,5, or 6. I can filter successfully when there is only a single value in each column. However once a column has multiple filters it fails.

Use a scenario where I want to filter on multiple POCs

Here is my code:

IEnumerable<IssueDataModel> filteredIssues = issueList;//Passed in dataset

var pocitemsArray = Array.Empty<string>();
var notificationitemsArray = Array.Empty<string>();

if (filterColumnPOCs == "Y")//This indicates the user has selected the POC Filter
{
    pocitemsArray = filterItemsPOCs.Split(';');//This is the string of users to filter on
    foreach (string currentItem in pocitemsArray)//Checking for each POC
    {
        filteredIssues = filteredIssues.Where(s => s.PocName1.Contains(currentItem) || s.originatorPocName.Contains(currentItem));
    }
}

if (filterColumnNotification == "Y")
{
    notificationitemsArray = filterItemsNotification.Split(',');
    foreach (string currentItem in notificationitemsArray)
    {
        filteredIssues = filteredIssues.Where(s => s.notificationType.Contains(currentItem));
    }
}

The issue is that when I filter the first POC, the second pass thru there won’t be any matches for the second POC, so there are no records returned.

If I try matching on the initial dataset (issuelist) it works, but then I can’t cascade one filter to the next filter. I.e filter the dataset for POC and then take that filtered dataset to Notification for filtering. Keep in mind have have 6 total filter loops but not all may be used at the same time.