Hashtable 的数组 出错！ 新人求救！

Question

Hashtable[] subtype=new Hashtable[4];
      subtype[0].Add("美发厅","19");
      subtype[0].Add("婚嫁服务","20");
      subtype[0].Add("美容院","21");
      subtype[1].Add("fda","1");
      subtype[2].Add("fdda","3");
      subtype[3].Add("ffda","2");出错
Object reference not set to an instance of an object.

Answer 1

Hashtable[] subtype=new Hashtable[4];
subtype[0]= new Hashtable;
subtype[1]= new Hashtable;
subtype[2]= new Hashtable;
subtype[3]= new Hashtable;
      subtype[0].Add("美发厅","19");
      subtype[0].Add("婚嫁服务","20");
      subtype[0].Add("美容院","21");
      subtype[1].Add("fda","1");
      subtype[2].Add("fdda","3");
      subtype[3].Add("ffda","2");

Answer 2

同上...HashTable是一个类,得先new 一下...