nodeJs之path模块

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注意:cmd+左键,点击模块名,进入模块声明部分

//导入系统的模块path,用于对文件路径进行处理
var path = require("path");

//格式化文件路径
var pathString = "./a//b/c/../d";
var str = path.normalize(pathString);
console.log(str);

//文件路径拼接,并规范化输出路径
var str = path.join("./","/a","//b","c","../","d");
console.log(str);

//__dirname:获取当前目录的绝对路径
console.log(__dirname);
var str = path.join(__dirname,"01-info.js");
console.log(str);

//判断是否是绝对路径
//注:判断以路径的开头为准,以斜杠开头的都是绝对路径
var result = path.isAbsolute('./a/b');
console.log(result);
var result = path.isAbsolute('../a/b');
console.log(result);
var result = path.isAbsolute('a/b');
console.log(result);
var result = path.isAbsolute('/a/b');
console.log(result);
var result = path.isAbsolute('/a/../b');
console.log(result);

//把相对路径转换成绝对路径
//1.默认以根目录作为起点
var str = path.resolve("a/b");
console.log(str);
var str = path.resolve("01-info.js");
console.log(str);
var str = path.resolve("/a");
console.log(str);
var str = path.resolve("./a");
console.log(str);
var str = path.resolve("../a");
console.log(str);
//2.以指定的路径开始
var str = path.resolve("/a","b");
console.log(str);
var str = path.resolve("a","b");
console.log(str);

//获取从 绝对路径1到绝对路径2 的相对路径
var str = path.relative("/a/b/c","/a/d/e");
console.log(str);

//获取当前文件所在的目录
var str = path.dirname();
console.log(str);

var str = path.dirname("a");
console.log(str);

var str = path.dirname("/a");
console.log(str);

var str = path.dirname("/a/b/c/d.txt");
console.log(str);

//获取路径的最后一部分
var str = path.basename("/a/b/c/d.txt");
console.log(str);

var str = path.basename("/a/b/c/index.html");
console.log(str);
var arr = str.split(".");
console.log(arr[0]);
//指定文件后缀,来获取文件名
var str = path.basename("/a/b/c/1.2.3.index.html",".html");
console.log(str);
//获取文件的后缀名(扩展名)
var str = path.extname("/a/b/c/1.2.3.index.html");
console.log(str);


//练习:写一个函数,提供文件路径,返回获取的文件名

function getFileName(pathString){
    return path.basename(pathString,path.extname(pathString));
}
console.log(getFileName("a/b/1.txt"));
console.log(getFileName("a/b/2.html"));

function getFileName2(pathString) {
    return path.parse(pathString).name;
}
console.log(getFileName2("a/b/1.txt"));
console.log(getFileName2("a/b/2.html"));

//路径解析(字符串转对象)
var obj = path.parse('/home/user/dir/file.txt');
console.dir(obj);

//路径编码(对象转字符串)
var str = path.format(obj);
console.log(str);