Null-Coalescing (??) Operator
string something = null;
string another = something ?? "Is currently null";
// another = Is currently null
Ternary (?) Operator
string name1 = "1234";
string name2 = "123456";
var valueLessThanFive = name1.Length < 5 ? name1 : name2;
// valueLessThanFive = 1234
String
Strip out Non Number / Alphabetic Characters
string word = "!@# Original Text 123 !@#";
string strippedWord = new String(word.Where( c => char.IsDigit(c) || char.IsLetter(c)).ToArray());
Assert.That(strippedWord, Is.EqualTo("OriginalText123");
Split string with sub string
var text = "this<>is<>it<>";
var splitText = text.Split(new[] { "<>" }, StringSplitOptions.None);
Convert to Title Case
var value = "some text here";
var result = CultureInfo.CurrentCulture.TextInfo.ToTitleCase(value.ToLower());
Creating a string for an array of characters
Previously I would do the following:
var chars = new [] {'a', 'b', 'c'};
var text = new string(chars);
A possibly cleaner syntaxt is…
var chars = new [] {'a', 'b', 'c'};
var text = string.Concat(chars);
DateTime
Parsing DateTime from String in a specific format
DateTime theDate = DateTime.ParseExact(dateText, "yyyyMMdd", CultureInfo.InvariantCulture);
Linq
Simulate a for Loop
var n = 10;
var values = Enumerable.Range(0, n).Select(DoSomething)
Private static decimal DoSomething(int n)
{
Return n * 0.1M;
}
Cartesian Product
Suppose you want to create the cartesian product of two lists (every possible combination between the two collections). This can be done as follows:
var listA = new List<int> { 1, 2, 3 };
var listB = new List<int> { 4, 5, 6 };
var cartesianLst = listA.SelectMany(a => listB.Select(b => new Tuple<int, int>(a, b)));
CSharp 6 Features
Expression Bodied Methods & Auto Properties
static public addNumbers(int a, int b) => a + b;
Dictionary Initialization
var colorMap = new Dictionary<string, ConsoleColor> {
["Error"] = ConsoleColor.Red,
["Information"] = ConsoleColor.Yellow
};
