C# Dictionary用法

var periodMapping = new Dictionary<string, int>
{
    {"第1節",0},
    {"第2節",1},
    {"第3節",2},
    {"第4節",3},
    {"1OT",4},
    {"2OT",5},
    {"3OT",6},
};

前面是key後面是value
只要用periodMapping[key]就能找到value