1. 程式人生 > >關Map遍歷取值解決辦法

關Map遍歷取值解決辦法

常用的幾種方式:


	Map<String, String> map = new HashMap<String, String>();
//第一種:普遍使用,二次取值
 
  for (String key : map.keySet()) {
   System.out.println("key= "+ key + " and value= " + map.get(key));
  }
  
  //第二種

  Iterator<Map.Entry<String, String>> it = map.entrySet().iterator();
  while (it.hasNext()) {
   Map.Entry<String, String> entry = it.next();
   System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue());
  }
  
  //第三種:推薦,尤其是容量大時

  for (Map.Entry<String, String> entry : map.entrySet()) {
   System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue());
  }

  //第四種

  for (String v : map.values()) {
   System.out.println("value= " + v);
  }
 }