等价于Golang中的readUIntLE？

Question

I need to read X (for example, 3) bytes at position Y in the buffer.

In Node.js, I'm doing this by using the Buffer class and the readUIntLE function.

For example: readUIntLE(position, 3).

What is the equivalent of that process in Golang?

Thanks!

Answer 1

For example,

package main

import "fmt"

func readUIntLE(buf []byte, offset, byteLength int) uint64 {
    var n uint64
    buf = buf[offset : offset+byteLength]
    if len(buf) > 8 {
        buf = buf[:8]
    }
    for i, b := range buf {
        n += uint64(b) << uint(8*i)
    }
    return n
}

func main() {
    buf := []byte{2, 4, 8, 16, 32, 64, 128, 255}
    fmt.Println(buf)
    fmt.Println(readUIntLE(buf, 0, 4))
    fmt.Println(readUIntLE(buf, 0, len(buf)))
    fmt.Println(readUIntLE(buf, len(buf)-1, 1))
}

Output:

[2 4 8 16 32 64 128 255]
268960770
18410785783142679554
255