函数示例:

func file_is_exists(f string) bool {
    _, err := os.Stat(f)
    if os.IsNotExist(err) {
        return false
    }
    return err == nil
}

user11617的示例不正确;即使在文件不存在的情况下，它也会报告文件存在，但存在其他类型的错误。

签名应该是Exists(string) (bool, error)。然后，碰巧的是，通话地点也没好到哪里去。

他编写的代码最好是:

func Exists(name string) bool {
    _, err := os.Stat(name)
    return !os.IsNotExist(err)
}

但我建议这样做:

func Exists(name string) (bool, error) {
  _, err := os.Stat(name)
  if os.IsNotExist(err) {
    return false, nil
  }
  return err != nil, err
}

    _, err := os.Stat(file)
    if err == nil {
        log.Printf("file %s exists", file)
    } else if os.IsNotExist(err) {
        log.Printf("file %s not exists", file)
    } else {
        log.Printf("file %s stat error: %v", file, err)
    }

正如在其他回答中提到的，可以通过使用os.OpenFile的不同标志来构造所需的行为/错误。事实上，os。Create只是这样做的一个合理的默认值简写:

// Create creates or truncates the named file. If the file already exists,
// it is truncated. If the file does not exist, it is created with mode 0666
// (before umask). If successful, methods on the returned File can
// be used for I/O; the associated file descriptor has mode O_RDWR.
// If there is an error, it will be of type *PathError.
func Create(name string) (*File, error) {
    return OpenFile(name, O_RDWR|O_CREATE|O_TRUNC, 0666)
}

你应该自己结合这些标志来获得你感兴趣的行为:

// Flags to OpenFile wrapping those of the underlying system. Not all
// flags may be implemented on a given system.
const (
    // Exactly one of O_RDONLY, O_WRONLY, or O_RDWR must be specified.
    O_RDONLY int = syscall.O_RDONLY // open the file read-only.
    O_WRONLY int = syscall.O_WRONLY // open the file write-only.
    O_RDWR   int = syscall.O_RDWR   // open the file read-write.
    // The remaining values may be or'ed in to control behavior.
    O_APPEND int = syscall.O_APPEND // append data to the file when writing.
    O_CREATE int = syscall.O_CREAT  // create a new file if none exists.
    O_EXCL   int = syscall.O_EXCL   // used with O_CREATE, file must not exist.
    O_SYNC   int = syscall.O_SYNC   // open for synchronous I/O.
    O_TRUNC  int = syscall.O_TRUNC  // truncate regular writable file when opened.
)

根据您选择的内容，您将得到不同的错误。

下面是一个示例，它将截断一个现有文件，或者当文件存在时失败。

openOpts := os.O_RDWR|os.O_CREATE
if truncateWhenExists {
    openOpts |= os.O_TRUNC // file will be truncated
} else {
    openOpts |= os.O_EXCL  // file must not exist
}
f, err := os.OpenFile(filePath, openOpts, 0644)
// ... do stuff

这是我在Go 1.16中检查文件是否存在的方法

package main

import (
    "errors"
    "fmt"
    "io/fs"
    "os"
)

func main () {
    if _, err:= os.Stat("/path/to/file"); errors.Is(err, fs.ErrNotExist){
        fmt.Print(err.Error())
    } else {
        fmt.Print("file exists")
    }
}

函数示例:

func file_is_exists(f string) bool {
    _, err := os.Stat(f)
    if os.IsNotExist(err) {
        return false
    }
    return err == nil
}