1.需要读取的文件
2.代码实现
@Test
public void test() {
FileReader fileReader = null;
BufferedReader bufferedReader = null;
int count = 0;
try {
fileReader = new FileReader("hello.txt");
bufferedReader = new BufferedReader(fileReader);
String str;
count = 0;
while ((str = bufferedReader.readLine()) != null){
char[] chars = str.toCharArray();
for (int i = 0; i < chars.length; i++) {
if(chars[i] >= 48 && chars[i] <= 57){
count++;
}
}
}
System.out.println("数字一共有:" + count + "个");
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if(bufferedReader != null){
bufferedReader.close();
}
if(fileReader != null){
fileReader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
3.运行结果