Useful Code snippets

snippets.cs

//Make a dictionary of distinct records
Dictionary<int, Record> records = findRecords(keys)
    .GroupBy(r => r.keyid)
    .ToDictionary(g => g.Key, g => g.First());
records.TryGetValue(key, out record);

//Make groups from lines
Lines.GroupBy(l => l.ReleaseDate, (k, g) => new { Key = k, Lines = g.ToList() } ).OrderBy(g => g.Key).ToList();

// Find and remove duplicates
IEnumerable<object> duplicates = Objects
    .Where(c => true) //Optional Filter
    .GroupBy(c => c.keyField) //Desired field to be unique
    .SelectMany(g => g.OrderBy(c => c.orderField).Skip(1)); //Field to ensure correct record is skipped
if (duplicates != null) Objects.RemoveRange(duplicates);

//Extension methods for finding max or min property.
public static T MaxBy<T, R>(this IEnumerable<T> en, Func<T, R> evaluate) where R : IComparable<R> {
    return en.Select(t => new Tuple<T, R>(t, evaluate(t)))
        .Aggregate((max, next) => next.Item2.CompareTo(max.Item2) > 0 ? next : max).Item1;
}
public static T MinBy<T, R>(this IEnumerable<T> en, Func<T, R> evaluate) where R : IComparable<R> {
    return en.Select(t => new Tuple<T, R>(t, evaluate(t)))
        .Aggregate((min, next) => next.Item2.CompareTo(min.Item2) < 0 ? next : min).Item1;
} // Usage:
list.MinBy(x => x.price);

snippets.js

//True when value is a representation of a number.
!isNaN(parseFloat(value)) && isFinite(value)

////AngularJS stuffs.
// Watch statement signature
$scope.$watch('', function (newValue, oldValue) { dostuff(); });

// Watch a property in an array of objects (slow, but working solution)
$scope.$watch(function($scope) {
    return $scope.listOfBigObjects.map(function(bigObject) {
        return bigObject.fieldICareAbout;
    });
}, function(newValues, oldValues) { //You'll end up watching an array of properties.
  dostuff(); 
}, true);