表达式

Func<int, int, int> add = (a, b) => (a + b);

模糊字符串格式

Console.WriteLine("{0:D10}", 2); // 0000000002

Dictionary<string, string> dict = new Dictionary<string, string> { 
    {"David", "C#"}, 
    {"Johann", "Perl"}, 
    {"Morgan", "Python"}
};

Console.WriteLine( "{0,10} {1, 10}", "Programmer", "Language" );

Console.WriteLine( "-".PadRight( 21, '-' ) );

foreach (string key in dict.Keys)
{
    Console.WriteLine( "{0, 10} {1, 10}", key, dict[key] );             
}

C#中有一些真正隐藏的关键字和特性与TypedReference未记录类相关。以下关键字未记录：

__制造商参考__重新键入__参考值__参数列表

使用示例：

// Create a typed reference
int i = 1;
TypedReference tr1 = __makeref(i);
// Get the type of a typed reference
Type t = __reftype(tr1);
// Get the value of a typed referece
int j = __refvalue(tr1, int); 
// Create a method that accepts and arbitrary number of typed references
void SomeMethod(__arglist) { ...
// Call the method
int x = 1;
string y = "Foo";
Object o = new Object();
SomeMethod(__arglist(x,y,o));
// And finally iterate over method parameters
void SomeMethod(__arglist) {
    ArgIterator ai = new ArgIterator(__arglist);
while(ai.GetRemainingCount() >0)
{
      TypedReference tr = ai.GetNextArg();
      Console.WriteLine(TypedReference.ToObject(tr));
}}

我喜欢在列表中查找以下内容：-

bool basketContainsFruit(string fruit) {
  return new[] { "apple", "orange", "banana", "pear" }.Contains(fruit);
}

而不是：-

bool basketContainsFruit(string fruit) {
  return fruit == "apple" || fruit == "orange" || fruit == "banana" ||
    fruit == "pear";
}

在实践中并没有太多，但根据搜索主题匹配项目的想法确实非常有用和简洁。

无特定顺序：

Lists<>
Mutex

Framework 3.5中的新属性定义快捷方式。

使用LINQ，可以根据参数创建新函数。如果你有一个非常经常执行的小函数，这很好，但是参数需要一些时间来计算。

    public Func<int> RandomGenerator
    {
        get
        {
            var r = new Random();
            return () => { return r.Next(); };
        }
    }

    void SomeFunction()
    {
        var result1 = RandomGenerator();

        var x = RandomGenerator;
        var result2 = x();
    }

不指定数组元素类型的数组初始化：

var pets = new[] { "Cat", "Dog", "Bird" };