public class File extends Object implements Serializable, Comparable<File> 构造方法: public File(String pathname) 按照完整路径实例化 public File(File parent, String child) 按照父路径和文件名实例化 成员: public static final String separator 目录分隔符 ('\'.'/'等) public static final
using System; using System.IO; class Test { public static void Main() { string path = @"c:\temp\MyTest.txt"; if (!File.Exists(path)) { // Create a file to write to. using (StreamWriter sw = File.CreateText(path)) { sw.WriteLine("Hello"
内部类的拓展 定义类or方法内部的类 最外层的类只能使用public和默认修饰 class Demo { class A { } public static void main(String[] args) { class B { } int a; } } 示例2: class Demo { //成员变量属于类的对象,只有类的对象存在时成员变量才存在 private int bb; class A { } public static void main(String[] args) { Demo
java.io.NotSerializableException: test.io.file.Student at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1183) at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347) at test.io.file.Demo4.test2(Demo4.java:36)