源代码在这里:
import java.io.*;public class TestFileInputStream { public static void main(String[] args) throws IOException {
int b = 0;
FileInputStream in = null;
try {
in = new FileInputStream("e:/java/1.txt");
} catch (FileNotFoundException e) {
System.out.println("找不到指定文件!");
System.exit(0);
e.printStackTrace();
}
long num = 0;
while((b=in.read()) !=-1){
System.out.print((char)b);
num++;
} }}
请教一下,为什么如果事先不声明 in,也就是说直接在try里面声明FileInputStream in = new FileInputStream("xx")
的话,下面在 while里面会找不到in?
import java.io.*;public class TestFileInputStream { public static void main(String[] args) throws IOException {
int b = 0;
FileInputStream in = null;
try {
in = new FileInputStream("e:/java/1.txt");
} catch (FileNotFoundException e) {
System.out.println("找不到指定文件!");
System.exit(0);
e.printStackTrace();
}
long num = 0;
while((b=in.read()) !=-1){
System.out.print((char)b);
num++;
} }}
请教一下,为什么如果事先不声明 in,也就是说直接在try里面声明FileInputStream in = new FileInputStream("xx")
的话,下面在 while里面会找不到in?
import java.io.*;public class TestFileInputStream { public static void main(String[] args) throws IOException {
int b = 0;
try {
FileInputStream in = new FileInputStream("e:/java/1.txt");
} catch (FileNotFoundException e) {
System.out.println("找不到指定文件!");
System.exit(0);
e.printStackTrace();
}
long num = 0;
while((b=in.read()) !=-1){
System.out.print((char)b);
num++;
} }}
try..catch处的自然不能访问咯。。