gistfile1.txt

// ==UserScript==
// @name          Amazon add cart link to search result
// @namespace     http://d.hatena.ne.jp/yujiorama
// @description	  Amazon add cart link to search result
// @include       http://www.amazon.co.jp/s/*
// @include       https://www.amazon.co.jp/s/*
// ==/UserScript==

var subscription_id = 'XXXXXXXXXXXXXXX';
var associate_id = 'XXXXXXXX-22';
function setAttribute(node, opt) {
    for (var x in opt) {
        node.setAttribute(x, opt[x]);
    }
    return node;
}
function createNode(tag, opt) {
    var n = document.createElement(tag);
    n = setAttribute(n, opt);
    return n;
}

function createHiddenNode(name, value) {
    return createNode('input', {'type': 'hidden', 'name': name, 'value': value});
}

(
 function() {
     if (console) {console.log('start: addcartbutton');}
     var items = document.evaluate("//div[@class='productTitle']/a[position()=1]", document, null, XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE, null);
     try {
         for (var i = 0; i < items.snapshotLength; ++i) {
             var node = items.snapshotItem(i);
             var href = node.getAttribute('href');
             var asin = href.match(/\/([0-9A-Z]{10})\//);
             if (asin) {
                 if (console) {console.log('asin: ' + asin[1]);}
                 var f = document.createElement("form");
                 f = setAttribute(f, {'method': 'post', 'action': '/gp/aws/cart/add.html', 'target': '_blank'});
                 var asinnode = createHiddenNode('ASIN.1', asin[1]);
                 var qnode = createHiddenNode('Quantity.1', '1');
                 var atagnode = createHiddenNode('AssociateTag', associate_id);
                 var subscnode = createHiddenNode('SubscriptionId', subscription_id);
                 var button = createNode('input', {'type': 'image', 'name': 'submit.add-to-cart', 'src': 'http://rcm-images.amazon.com/images/G/09/extranet/associates/buttons/remote-buy-jp1.gif', 'alt': 'カートに追加'});
                 node.parentNode.appendChild(f);
                 f.appendChild(asinnode);
                 f.appendChild(qnode);
                 f.appendChild(atagnode);
                 f.appendChild(subscnode);
                 f.appendChild(button);

             }
         }
     }
     catch (e) {
         if (console) { console.log('error: ' + e);}
         dump( 'Error: Document tree modified during iteraton ' + e );
     }
     if (console) {console.log('end: addcartbutton');}
 }
)();