微信支付訂單生產方法：

    /**
     * 根據您的訂單資訊 生成 微信產品支付訂單資訊
     */
    private String createWeChatOrder() {
        StringBuffer xml = new StringBuffer();
        try {
            String nonceStr = genNonceStr();
            xml.append("</xml>");
            List<KeyValue> packageParams = new LinkedList<KeyValue>();
            packageParams.add(new KeyValue("appid", APP_ID));
            packageParams.add(new KeyValue("attach", orderType));
            packageParams.add(new KeyValue("body", "天鑫計費-網咖充值"));
            packageParams.add(new KeyValue("mch_id", MCH_ID));
            packageParams.add(new KeyValue("nonce_str", nonceStr));
            packageParams.add(new KeyValue("notify_url", callBackUrl));
            packageParams.add(new KeyValue("out_trade_no", orderOn));
            packageParams.add(new KeyValue("spbill_create_ip", "127.0.0.1"));
            packageParams.add(new KeyValue("total_fee", getTotalFee(price)));
            // packageParams.add(new KeyValue("total_fee", price));
            packageParams.add(new KeyValue("trade_type", "APP"));
            String sign = genPackageSign(packageParams);
            packageParams.add(new KeyValue("sign", sign));
            String xmlstring = toXml(packageParams);

            return xmlstring;

//            return new String(xmlstring.toString().getBytes(), "ISO8859-1");
            // return xmlstring;
        } catch (Exception e) {
            return null;
        }
    }

使用中文body報錯：簽名錯誤解決方法：

直接返回xmlstring即可。不需要新增字元格式“ISO8859-1”