int rowNum = 0;
PrintWriter rowNumPW = null;
try {
rowNumPW = new PrintWriter(new BufferedWriter(new FileWriter("out.txt",false)));
} catch (IOException ex) {
ex.printStackTrace();
}
for(int i = 0; i< 8; i++){
rowNum++
rowNumPW.print(rowNum);
rowNumPW.flush();
}
rowNumPW.close();为什么每次输出到 out.txt 文件的数字都是添加到上一个数字的后面,而不是直接把原来的数字给覆盖掉呀!!!
int rowNum = 0;
PrintWriter rowNumPW = null;
try {
rowNumPW = new PrintWriter(new BufferedWriter(new FileWriter("out.txt",false)));
} catch (IOException ex) {
ex.printStackTrace();
}
for(int i = 0; i< 8; i++){
rowNum++
rowNumPW.print(rowNum);
rowNumPW.flush();
}
rowNumPW.close();
你的值一直都没有变呀,
for(int i = 0; i< 8; i++){
rowNum++ //这里少了个分号;
rowNumPW.print(rowNum);
rowNumPW.flush();另外,new FileWriter("out.txt",false))); //将false改成true
最笨的方法就是直接File类的delete了。
PrintWriter rowNumPW = null;for(int i = 0; i< 8; i++){
try {
rowNumPW = new PrintWriter(new BufferedWriter(new FileWriter("out.txt",false)));
} catch (IOException ex) {
ex.printStackTrace();
}
rowNum++;
rowNumPW.print(rowNum);
rowNumPW.flush();
rowNumPW.close()
}