Uint8Array to hex string.. and back... and some tests....

gistfile1.txt

        let b2h = []
        for(let i=0;i<256;i++)b2h[i]=i.toString(16).padStart(2,"0")
        let arrayToHex=(a)=>{
           let hex = new Array(a.length)
           for(let i=0,l=a.length;i<l;i++)hex[i]=b2h[a[i]]
           return hex.join('')
        }
        let h2b = {}
        for(let i=0;i<256;i++)h2b[i.toString(16).padStart(2,"0")]=i;
        let splitHex = new RegExp('.{1,' + 2 + '}', 'g');
        let hexToArray=(hex)=>{
           hex = hex.match(splitHex);
           let a = new Uint8Array(hex.length)
           for(let i=0,l=a.length;i<l;i++)a[i]=h2b[hex[i]]
           return a
        }
        //Test: Convert a Uint8Array to hex and back
        let mu = new Uint8Array([123,234,125,255])
        let hex = arrayToHex(mu)
        let out = hexToArray(hex)
        console.log(mu, " converts to: ", hex, " decodes to:", out)

        let base64test="MOfmaofmosd";
        let arr = btoa( base64test )
        let res = atob(arr);
        console.log(res)