C# Filtering employee ID's from a list to modify a query

Learning C# here. I have a monthly process form whereby one can select to process salaries for all employees or select the employees to process for using radio buttons (SAP B1 开发者_StackOverflowform using screenpainter).

One is able to open a form to select employees and the employee ID's are sent to this monthly process form and are stored in a list.

//Method to retrieve string values from child form
public void GetFilteredIds(List<string> idValues)
{
    List<string> employeeIDs = new List<string>();

    employeeIDs = idValues;
}

I wanted to filter this query on the monthly process form that selects ALL emp IDs

//Query database
var salaryFitments = salaryFitmentService.GetAllSalaryFitments();

var employeeIdList = (from sf in salaryFitments select sf.U_Employee_ID).Distinct();

such that I have something similar to this:

var k = from id in employeeIdList
           where employeeIDs.Contains(id)
           select id;

How do I write my code such that just before processing (hitting a process button), I have an if statement to check if its a monthly process for all or just a few selected

if (_selectedEmployees.Selected == true)
{
   ...code to write
}
else
{
   ...code to write
}

_selectedEmployees refers to private SAPbouiCOM.OptionBtn _selectedEmployees;

Just before processing

if (employeeIdList.Any())
            {  ............

I hope my question is clear enough

Not 100% sure what you're after, but would this help:

// Code to see if the 'all employees' radiobutton is selected.

var k = from id in employeeIdList
        where AllSelected || employeeIDs.Contains(id)
        select id;

You wouldn't have to duplicate your query then.