Bitcoin testnet transaction example when using browser

bitcoin-testnet-transaction.js

// For browser
 $.getJSON("https://chain.so/api/v2/get_tx_unspent/BTCTEST/"+bitcoinAddress,function(result){
            var last = result.data.txs.length - 1;
            console.log('Current:' + last + ' ' + address);
            var unspent_txid = result.data.txs[last].txid;

            var unspent_vout = result.data.txs[last].output_no;
            txb = new Bitcoin.TransactionBuilder(network);

            txb.addInput(unspent_txid, unspent_vout);

            value = Number(result.data.txs[last].value * 100000000);

            pay = 0.005 * 100000000;
            change = parseInt(value - pay);

            var commit = new Buffered("Test");

            var dataScript = Bitcoin.script.nullData.output.encode(commit);

            txb.addOutput(dataScript, 0);
            txb.addOutput(address,change);

            txb.sign(0, keyPair);

            var txRaw = txb.build();
            var txHex = txRaw.toHex();

            console.log('hex',txHex);
            postdata = { tx_hex : txHex };
            postTransaction(itemid);
        });

function postTransaction(itemid){
    $.post("https://chain.so/api/v2/send_tx/BTCTEST/",postdata,function(result){
        if(result.status ==="fail"){
            setTimeout(function(){
                makeTransaction(postTransaction());
            },5000);
        }else{
           console.log(result.data.txid);
        }
    })
}