LINQ basics

1. Obtain the data sources(s)
2. Create the query
   1. Declare variable var query = the following
   2. From variable Name in obtained data Source [//Declaration]
   3. Where variable name. Property == or > or < or any operator against any value [// criteria and filtering]
   4. Orderby variable name. Property, variable name. Property [//sorting]
   5. Select (variable name or variable name * 10 (any expression) or new { property1= val1 , property2 = val2 } (anonymous type) [// projection]
3. Execute the query
   1. ToList()
   2. ToArraay()
   3. Foreach and access the query result

Example:

var files = new DirectoryInfo(@"c:\\").GetFiles();

var query = from file in files
            where file.Length > 0
            orderby file.Name, file.Length
            select new 
            {
                Name = file.Name,
                Length = file.Length,
                CreatedDate = file.CreationTime
            };

var my = query.ToList();

foreach (var myFileInfo in query)
{
    Console.WriteLine(myFileInfo.Name);
}