Create a dictionary on a list with grouping

Question

I have the following object in a list:

public class DemoClass
{
    public int GroupKey { get; set; }
    public string DemoString { get; set; }
    public o         


        

Answer 1

var groupedDemoClasses = (from demoClass in mySepcialVariableWhichIsAListOfDemoClass
                          group demoClass by demoClass.GroupKey
                          into groupedDemoClass
                          select groupedDemoClass).ToDictionary(gdc => gdc.Key, gdc => gdc.ToList());

This one will work !!!