nodejs 数字字节转换操作

function number2Bytes(i) {
var arr = new Int32Array(1);
arr[0] = 0;
var buf = Buffer.from(arr.buffer, 'hex');
buf.writeInt32BE(i);

console.log("buf:", buf);
console.log("buffer length :", buf.length); 
var iNumber = buf.readInt32BE();
console.log("iNumber:", iNumber);
return buf;
};