golang判断文本文件是否是BOM格式的方法详解

package main
import (
        "fmt"
        "io/ioutil"
        "os"
)
func checkBOMUTF8(file string) bool {
        f, err := os.Open(file)
        if err != nil {
            fmt.Println("Error:", err)
            os.Exit(1)
        }
        defer f.Close()
        // Read the first three bytes
        b := make([]byte, 3)
        _, err = f.Read(b)
        if err != nil {
            fmt.Println("Error:", err)
            os.Exit(1)
        }
        // Check if the bytes match the UTF-8 BOM
        if b[0] == 0xEF && b[1] == 0xBB && b[2] == 0xBF {
            return true
        }
        return false
}
func main() {
        if checkBOMUTF8("test.txt") {
            fmt.Println("The file is in BOM format.")
        } else {
            fmt.Println("The file is not in BOM format.")
        }
}

package main
import (
        "fmt"
        "io/ioutil"
        "os"
)
func checkBOMUTF16(file string) bool {
        f, err := os.Open(file)
        if err != nil {
            fmt.Println("Error:", err)
            os.Exit(1)
        }
        defer f.Close()
        // Read the first two bytes
        b := make([]byte, 2)
        _, err = f.Read(b)
        if err != nil {
            fmt.Println("Error:", err)
            os.Exit(1)
        }
        // Check if the bytes match the UTF-16 BOM (Little Endian)
        if b[0] == 0xFF && b[1] == 0xFE {
            return true
        }
        // Check if the bytes match the UTF-16 BOM (Big Endian)
        if b[0] == 0xFE && b[1] == 0xFF {
            return true
        }
        return false
}
func main() {
        if checkBOMUTF16("test.txt") {
            fmt.Println("The file is in UTF-16 BOM format.")
        } else {
            fmt.Println("The file is not in UTF-16 BOM format.")
        }
}

package main
import (
        "fmt"
        "io/ioutil"
        "os"
)
func checkBOMUTF32(file string) bool {
        f, err := os.Open(file)
        if err != nil {
            fmt.Println("Error:", err)
            os.Exit(1)
        }
        defer f.Close()
        // Read the first four bytes
        b := make([]byte, 4)
        _, err = f.Read(b)
        if err != nil {
            fmt.Println("Error:", err)
            os.Exit(1)
        }
        // Check if the bytes match the UTF-32 BOM (Little Endian)
        if b[0] == 0xFF && b[1] == 0xFE && b[2] == 0x00 && b[3] == 0x00 {
            return true
        }
        // Check if the bytes match the UTF-32 BOM (Big Endian)
        if b[0] == 0x00 && b[1] == 0x00 && b[2] == 0xFE && b[3] == 0xFF {
            return true
        }
        return false
}
func main() {
        if checkBOMUTF32("test.txt") {
            fmt.Println("The file is in UTF-32 BOM format.")
        } else {
            fmt.Println("The file is not in UTF-32 BOM format.")
        }
}