javascript JavaScript UUID Generator - 非常非常独特

Posted 2021-05-04

(() => {
    let lut = []; for (let i=0; i<256; i++) { lut[i] = (i<16?'0':'')+(i).toString(16); }
    const d0 = Math.random()*0xffffffff|0;
    const d1 = Math.random()*0xffffffff|0;
    const d2 = Math.random()*0xffffffff|0;
    const d3 = Math.random()*0xffffffff|0;
    return lut[d0&0xff]+lut[d0>>8&0xff]+lut[d0>>16&0xff]+lut[d0>>24&0xff]+'-'+
      lut[d1&0xff]+lut[d1>>8&0xff]+'-'+lut[d1>>16&0x0f|0x40]+lut[d1>>24&0xff]+'-'+
      lut[d2&0x3f|0x80]+lut[d2>>8&0xff]+'-'+lut[d2>>16&0xff]+lut[d2>>24&0xff]+
      lut[d3&0xff]+lut[d3>>8&0xff]+lut[d3>>16&0xff]+lut[d3>>24&0xff];
})();