Learn the file operation functions in Go language and implement the folder copy function

Go language is a fast, concise, and reliable programming language. Its powerful file operation functions make file copying abnormal. Simple. In this article, we will learn the file operation functions in the Go language and demonstrate its power by implementing the folder copy function.

The Go language provides the os package and the io/ioutil package to handle file operations. We first use the functions in the os package to complete the folder copy function.

First, we need to declare a function to copy a folder, named copyFolder. This function receives two parameters, namely source folder path source and target folder path target. Inside the function, we need to use the os.Stat function to get the source folder information and check whether the source folder exists. The code is as follows:

package main

import (
    "fmt"
    "io"
    "os"
    "path/filepath"
)

func copyFolder(source, target string) error {
    sourceInfo, err := os.Stat(source)
    if err != nil {
        return err
    }

    if !sourceInfo.IsDir() {
        return fmt.Errorf("%s is not a valid directory", source)
    }

    // 在此處執(zhí)行拷貝文件夾的操作
    return nil
}

Next, we will implement the specific operation of copying the folder. First, we need to use the os.MkdirAll function to create the target folder. If the target folder already exists, this step will be skipped. Then, we need to use the os.ReadDir function to read all files and folders under the source folder and operate them accordingly. The code is as follows:

func copyFolder(source, target string) error {
    // ...

    err = os.MkdirAll(target, sourceInfo.Mode())
    if err != nil {
        return err
    }

    entries, err := os.ReadDir(source)
    if err != nil {
        return err
    }

    for _, entry := range entries {
        sourcePath := filepath.Join(source, entry.Name())
        targetPath := filepath.Join(target, entry.Name())

        if entry.IsDir() {
            err = copyFolder(sourcePath, targetPath)
            if err != nil {
                return err
            }
        } else {
            err = copyFile(sourcePath, targetPath)
            if err != nil {
                return err
            }
        }
    }

    return nil
}

Now, we need to implement the function copyFile that copies files. This function receives two parameters, namely source file path source and target file path target. First, we need to open the source file using the os.Open function and close the file at the end of the function. We then need to create the target file using the os.Create function and close the file at the end of the function. Finally, we need to use the io.Copy function to copy the source file contents to the destination file. The code is as follows:

func copyFile(source, target string) error {
    sourceFile, err := os.Open(source)
    if err != nil {
        return err
    }
    defer sourceFile.Close()

    targetFile, err := os.Create(target)
    if err != nil {
        return err
    }
    defer targetFile.Close()

    _, err = io.Copy(targetFile, sourceFile)
    if err != nil {
        return err
    }

    return nil
}

Finally, call the copyFolder function in the main function and pass in the source folder path and target folder path. The code example is as follows:

func main() {
    err := copyFolder("source_folder", "target_folder")
    if err != nil {
        fmt.Println(err)
        return
    }

    fmt.Println("文件夾拷貝成功")
}

The above code implements the folder copy function in Go language. By learning the file operation functions of the Go language, we can easily process files and folders. I hope this article will be helpful for everyone to learn the file operation functions of Go language.

The above is the detailed content of Learn the file operation functions in Go language and implement the folder copy function. For more information, please follow other related articles on the PHP Chinese website!