使用golang阅读tar文件的内容而不解压

Question

我已经能够遍历tar文件中的文件，但我坚持如何以字符串形式读取这些文件的内容。我想知道如何以字符串形式打印文件的内容？

这是我的代码如下

package main 

import (
    "archive/tar" 
    "fmt" 
    "io" 
    "log" 
    "os" 
    "bytes" 
    "compress/gzip" 
) 

func main() { 

    file, err := os.Open("testtar.tar.gz") 

    archive, err := gzip.NewReader(file) 

    if err != nil { 
     fmt.Println("There is a problem with os.Open") 
    } 
    tr := tar.NewReader(archive) 

    for { 
     hdr, err := tr.Next() 
     if err == io.EOF { 
      break 
     } 
     if err != nil { 
      log.Fatal(err) 
     } 

     fmt.Printf("Contents of %s:\n", hdr.Name) 
    } 

} 

Answer 1

只需使用tar.Reader作为io.Reader对要读取每个文件。

tr := tar.NewReader(r) 

// get the next file entry 
h, _ := tr.Next() 

如果您需要将整个文件作为一个字符串：

// read the complete content of the file h.Name into the bs []byte 
bs, _ := ioutil.ReadAll(tr) 

// convert the []byte to a string 
s := string(bs) 

如果需要逐行读取，那么这将是更好的：

// create a Scanner for reading line by line 
s := bufio.NewScanner(tr) 

// line reading loop 
for s.Scan() { 

    // read the current last read line of text 
    l := s.Text() 

    // ...and do something with l 

} 

// you should check for error at this point 
if s.Err() != nil { 
    // handle it 
} 

Answer 2

与一些帮助官方网站这是我以前的意图。应特别关注从字节到字符串转换的底部。

package main 

import (
    "archive/tar" 
    "fmt" 
    "io" 
    "log" 
    "os" 
    "bytes" 
    "compress/gzip" 
) 

func main() { 

    file, err := os.Open("testtar.tar.gz") 

    archive, err := gzip.NewReader(file) 

    if err != nil { 
     fmt.Println("There is a problem with os.Open") 
    } 
    tr := tar.NewReader(archive) 

    for { 
     hdr, err := tr.Next() 
     if err == io.EOF { 
      break 
     } 
     if err != nil { 
      log.Fatal(err) 
     } 

     fmt.Printf("Contents of %s:\n", hdr.Name) 

     //Using a bytes buffer is an important part to print the values as a string 

     bud := new(bytes.Buffer) 
     bud.ReadFrom(tr) 
     s := bud.String() 
     fmt.Println(s) 
     fmt.Println() 
    } 

}