github.com/qiuhoude/go-web@v0.0.0-20220223060959-ab545e78f20d/prepare/08_file/opfile/ioutil_test.go (about)

     1  package opfile
     2  
     3  import (
     4  	"fmt"
     5  	"io/ioutil"
     6  	"strings"
     7  )
     8  
     9  func ioutilDemo() {
    10  	/*
    11  		   ioutil包：
    12  			   ReadFile()
    13  			   WriteFile()
    14  			   ReadDir()
    15  			   ..
    16  	*/
    17  
    18  	//1.读取文件中的所有的数据
    19  	//fileName1 := "/Users/ruby/Documents/pro/aa.txt"
    20  	//data, err := ioutil.ReadFile(fileName1)
    21  	//fmt.Println(err)
    22  	//fmt.Println(string(data))
    23  
    24  	//2.写出数据
    25  	//fileName2:="/Users/ruby/Documents/pro/bbb.txt"
    26  	//s1:="helloworld面朝大海春暖花开"
    27  	//err:=ioutil.WriteFile(fileName2,[]byte(s1),0777)
    28  	//fmt.Println(err)
    29  
    30  	//3.
    31  	s2 := "qwertyuiopsdfghjklzxcvbnm"
    32  	r1 := strings.NewReader(s2)
    33  	data, _ := ioutil.ReadAll(r1)
    34  	fmt.Println(data)
    35  
    36  	//4.ReadDir(),读取一个目录下的子内容：子文件和子目录，但是仅有一层
    37  	dirName := "/Users/ruby/Documents/pro"
    38  	fileInfos, _ := ioutil.ReadDir(dirName)
    39  	fmt.Println(len(fileInfos))
    40  	for i := 0; i < len(fileInfos); i++ {
    41  		//fmt.Printf("%T\n",fileInfos[i])
    42  		fmt.Println(i, fileInfos[i].Name(), fileInfos[i].IsDir())
    43  	}
    44  
    45  }