[] 运算符被称为索引器。
索引器允许对对象进行索引,例如数组。当您为一个类定义一个索引器时,该类的行为类似于一个虚拟数组。然后,您可以使用数组访问运算符([ ])访问该类的实例。
索引器可以被重载。索引器也可以声明多个参数,并且每个参数可以是不同的类型。索引不一定必须是整数。
示例1
'static void Main(string[] args){
IndexerClass Team = new IndexerClass();
Team[0] = "A";
Team[1] = "B";
Team[2] = "C";
Team[3] = "D";
Team[4] = "E";
Team[5] = "F";
Team[6] = "G";
Team[7] = "H";
Team[8] = "I";
Team[9] = "J";
for (int i = 0; i < 10; i++){
Console.WriteLine(Team[i]);
}
Console.ReadLine();
}
class IndexerClass{
private string[] names = new string[10];
public string this[int i]{
get{
return names[i];
} set {
names[i] = value;
}
}
}
输出
'A
B
C
D
E
F
G
H
I
J
Example 2
重写 []
'static class Program{
static void Main(string[] args){
IndexerClass Team = new IndexerClass();
Team[0] = "A";
Team[1] = "B";
Team[2] = "C";
for (int i = 0; i < 10; i++){
Console.WriteLine(Team[i]);
}
System.Console.WriteLine(Team["C"]);
Console.ReadLine();
}
}
class IndexerClass{
private string[] names = new string[10];
public string this[int i]{
get{
return names[i];
}
set{
names[i] = value;
}
}
public string this[string i]{
get{
return names.Where(x => x == i).FirstOrDefault();
}
}
}
输出
'A
B
C
C