Salesforce: リストビューに一括削除ボタン

DeleteMulti.js

{!REQUIRESCRIPT('/soap/ajax/33.0/connection.js')};

var ids = {!GETRECORDIDS($ObjectType.Lead)},
    idsStr = ids.toString().replace(/,/g, "','");
    query = "SELECT Name FROM Lead WHERE Id IN ('" + idsStr + "')",
    records = sforce.connection.query(query).getArray('records');

if (records.length === 0) { 
    alert('1つ以上選択してください');
} else {
    var msg = records.length + '件のリードを削除します。\nよろしいですか？\n\n';
    for (var i = 0; i < records.length; i++) {
        msg += (i + 1) + ': ' + records[i].Name + '\n';
    }
    if (window.confirm(msg)) {
        sforce.connection.deleteIds(ids); 
        window.location.reload(); 
    }
}