作者SST2000 (BMW 428i)
看板java
標題[問題]請問關於文件讀取行的問題!!!
時間Fri Jan 24 03:02:00 2020
我有一個文件*.txt檔裡面內容是這樣
In this below-sea-level basin, steady drought and record summer heat make
Death Valley a
land of extremes. Yet, each extreme has a striking contrast. Towering peaks
are frosted with
winter snow. Rare rainstorms bring vast fields of wildflowers. Lush oases
harbor tiny fish
and refuge for wildlife and humans. Despite its morbid name, a great
diversity of life survives
in Death Valley.
在程式碼裡面用
while(bufferedReader.readLine() != null)
{
System.out.println(bufferedReader.readLine());
}
結果只會顯示第二行和第四行
land of extremes. Yet, each extreme has a striking contrast. Towering peaks
are frosted with
and refuge for wildlife and humans. Despite its morbid name, a great
diversity of life survives
但是如果用
String str = null;
while((str=bufferedReader.readLine()) != null)
{
System.out.println(str);
}
就可以顯示文件全部的內容,但是請問這兩種方式在邏輯上好像
沒甚麼不一樣????請問為什麼會有這樣的狀況?
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1F：推 vavamos: 看一下你哪邊有用到readLine方法 用debug模式查就知道了 01/24 03:18
2F：→ dennisxkimo: 例1：while讀 print讀 while讀 print 讀 所以只 01/24 05:49
3F：→ dennisxkimo: 有雙數行印出 01/24 05:49
4F：→ dennisxkimo: 例2：while讀進str print已讀進str (loop) 01/24 05:51
5F：→ dennisxkimo: 就會每行印出 01/24 05:54