字符串轉為ArrayBuffer的方法

string2buffer: function (str) {
    // 首先將字符串轉為16進制
    let val = ""
    for (let i = 0; i < str.length; i++) {
      if (val === '') {
        val = str.charCodeAt(i).toString(16)
      } else {
        val += ',' + str.charCodeAt(i).toString(16)
      }
    }
    // 將16進制轉化為ArrayBuffer
    return new Uint8Array(val.match(/[\da-f]{2}/gi).map(function (h) {
      return parseInt(h, 16)
    })).buffer
  }