java获取文件名（前缀和后缀以及全名）

梦里梦外; 2022-02-18 15:21 378阅读 0赞

package com.ratel.test;
    
    import java.io.File;
    
    /** * @业务描述： * @package_name： com.ratel.test * @project_name： ssm * @author： ratelfu@qq.com * @copyright (c) ratelfu 版权所有 */
    public class MyTest { 
    
        public static void main(String[] args) { 
            String fileName = " G:\\Java_Source\\navigation_tigra_menu\\demo1\\img\\lev1_arrow.gif ";
    
            methodOne(fileName);
            System.out.println("====================");
            methodtwo(fileName);
            System.out.println("====================");
            methodThree(fileName);
            System.out.println("====================");
            getFullNameOne();
            System.out.println("====================");
            getFullNameTwo();
            System.out.println("====================");
            getPrefixNameOne();
            System.out.println("====================");
            getPrefixNameTwo();
            System.out.println("====================");
            getPrefixNameThree();
            System.out.println("====================");
            getSuffixNameOne();
            System.out.println("====================");
            getSuffixNameTwo();
    
        }
    
        public static void methodOne(String fileName) { 
    
            File tempFile = new File(fileName.trim());
            String fName = tempFile.getName();
            System.out.println("方法一的：fileName = " + fName);
    
        }
    
        public static void methodtwo(String fileName) { 
    
            String fName = fileName.trim();
            String NameOne = fName.substring(fName.lastIndexOf("/") + 1);
            System.out.println("方法二的第一种：fileName = " + NameOne);
            String NameTwo = fName.substring(fName.lastIndexOf("\\") + 1);
            System.out.println("方法二的第二种：fileName = " + NameTwo);
    
        }
    
        public static void methodThree(String fileName) { 
    
            String fName = fileName.trim();
            ///**split里面必须是正则表达式，"\\"的作用是对字符串转义*/
            String temp[] = fName.split("\\\\");
            String tempName = temp[temp.length - 1];
            System.out.println("方法三的：fileName = " + tempName);
    
        }
    
        //获取文件的全名：
    
        public static void getFullNameOne(){ 
            String fileName="E:\\file.docx";
            String temp[]=fileName.split("\\\\");
            String fileNameNow=temp[temp.length-1];
            System.out.println(fileNameNow);
        }
    
        public static void getFullNameTwo(){ 
            String fileName="E:\\file.pdf";
            String fileNameNow = fileName.substring(fileName.lastIndexOf("\\")+1);
            System.out.println(fileNameNow);
        }
    
        //获取文件前缀名
    
        public static void getPrefixNameOne(){ 
    
            String filename = "file.docx";
            String caselsh = filename.substring(0,filename.lastIndexOf("."));
            System.out.println(caselsh);
        }
    
        public static void getPrefixNameTwo(){ 
            String filename = "file.docx";
            String caselsh = filename.split("\\.")[0];
            System.out.println(caselsh);
        }
        //本方法主要是为了解决split函数不能截取"." 一种曲线救国策略，简单方式是上一种用"\\"转义解决
        public static void getPrefixNameThree(){ 
            String filename = "file.docx";
            //要是写成：filename.replace(".", "￥");是没有效果的，
            filename = filename.replace(".", "￥");
            String caselsh = filename.split("￥")[0];
            System.out.println(caselsh);
        }
        //获取文件后缀名
    
        public static void getSuffixNameOne(){ 
            String filename = "file.txt";
            String[] strArray = filename.split("\\.");
            int suffixIndex = strArray.length -1;
            System.out.println(strArray[suffixIndex]);
        }
        public static void getSuffixNameTwo(){ 
            String fileName="file.txt";
            String fileTyle=fileName.substring(fileName.lastIndexOf(".")+1,fileName.length());
            System.out.println(fileTyle);
        }
    }