MiniprogramBle/utils/util.js

function formatTime(date) {
  const year = date.getFullYear()
  const month = date.getMonth() + 1
  const day = date.getDate()
  const hour = date.getHours()
  const minute = date.getMinutes()
  const second = date.getSeconds()

  return [year, month, day].map(formatNumber).join('/') + ' ' + [hour, minute, second].map(formatNumber).join(':')
}

function formatNumber(n) {
  n = n.toString()
  return n[1] ? n : '0' + n
}


function uint8ArrayToString(fileData){
  let dataString = "";
  for (let i = 0; i < fileData.length; i++) {
    dataString += String.fromCharCode(fileData[i]);
  }
  return dataString
}

function stringToUint8Array(str){
        let arr = [];
        for (let i = 0, j = str.length; i < j; ++i) {
            arr.push(str.charCodeAt(i));
        }
        let tmpUint8Array = new Uint8Array(arr);
        return tmpUint8Array
}
 

// 微信官方给的ArrayBuffer转十六进制示例
function ab2hex(buffer) {
  let hexArr = Array.prototype.map.call(
    new Uint8Array(buffer),
    function (bit) {
      return ('00' + bit.toString(16)).slice(-2)
    }
  )
  return hexArr.join(',');
}

//转成可展会的文字
function hexCharCodeToStr(hexCharCodeStr) {
    let trimedStr = hexCharCodeStr.trim();
    let rawStr = trimedStr.substr(0, 2).toLowerCase() === '0x' ? trimedStr.substr(2) : trimedStr;
    let len = rawStr.length;
    let curCharCode;
    let resultStr = [];
    for (let i = 0; i < len; i = i + 2) {
        curCharCode = parseInt(rawStr.substr(i, 2), 16);
        resultStr.push(String.fromCharCode(curCharCode));
    }
    return resultStr.join('');
}

//转换成需要的格式
function buf2string(buffer) {
    let arr = Array.prototype.map.call(new Uint8Array(buffer), x => x)
    
	return arr.map((char, i) => {
            return String.fromCharCode(char);
    }).join('');
}
	
function decodeHexNibble(c) {
        if (c >= 48 && c <= 57) {
            return c - 48;
        } else if (c >= 65 && c <= 70) {
            return c - 65 + 10;
        } else {
            return c >= 97 && c <= 102 ? c - 97 + 10 : -1;
        }
}
	
function decodeHexByte(s, pos) {
        let hi = decodeHexNibble(s.charCodeAt(pos));
        let lo = decodeHexNibble(s.charCodeAt(pos + 1));
        return ((hi << 4) + lo);
}

function hexStringToBytesWithPadding(str, byteLen, padding) {
      let len = str.length  
      let length = 2 * byteLen
        
        if (length >= len && (length & 1) == 0) {
            if (length == 0) {
                return [0];
            } else {
                let bytes = new Uint8Array(length >>> 1);				

                for(let i = 0; i < len; i += 2) {
                    bytes[i >>> 1] = decodeHexByte(str, i);	
                }

                for(let i = 0; i < byteLen-len/2; i++)
                    bytes[len/2+i] = padding;

                return bytes;
            }
        }  
		else
			return [0];
}	
	
	
function hexStringToBytes(str) {
		let s = str;	
		if(s.length < 12)
		{
		   let tmp = 12-s.length
		   for(let i = 0; i< tmp; i++)
              s = "0" + s;			   
		}
		else
			s = str.substr(s.length-12, s.length);

		let start = 0
		let length = s.length
		
        if (length >= 0 && (length & 1) == 0) {
            if (length == 0) {
                return new byte[0];
            } else {
                let bytes = new Uint8Array(length >>> 1);

                for(let i = 0; i < length; i += 2) {
                    bytes[i >>> 1] = decodeHexByte(s, start + i);
                }

                return bytes;
            }
        }
		else
			return [0];		
}	

module.exports = {
  formatTime: formatTime,
  uint8ArrayToString: uint8ArrayToString,
  stringToUint8Array: stringToUint8Array, 
  ab2hex: ab2hex,
  hexCharCodeToStr,
  hexCharCodeToStr: buf2string,
  decodeHexNibble,
  decodeHexNibble: decodeHexByte,
  hexStringToBytesWithPadding: hexStringToBytesWithPadding,
  hexStringToBytes: hexStringToBytes
}