jquery code, using the formData object

var formData = new FormData();
        //formData.append("shopImg", shopImg);
        //formData.append("shopStr", JSON.stringify(shop));
        var verifyCodeActual = $("-sharpj_captcha").val();
        if (!verifyCodeActual) {
            $.toast("");
            return;
        }
        formData.append("verifyCodeActual", verifyCodeActual);

        $.ajax({
            url : (isEdit ? editShopUrl : registerShopUrl),
            type : "POST",
            data : formData,
            contentType: "application/x-www-form-urlencoded",
            cache: false,
            processData: false,
            success : function(data) {
                if (data.success) {
                    console.log(data);
                    $.toast("");
                    $("-sharpcaptcha_img").click();
                } else {
                    $.toast("");
                    console.log(data);
                    $("-sharpcaptcha_img").click();
                }
            }
        });

after successfully post to the server, the Form Data read by chrome

spring key=verifyCodeActualnull