我在一个www.example.com web应用程序中实现了一个弹出窗口asp.net，允许用户选择一些内容，然后生成一个电子邮件模板。在完成所有必填字段后，用户通过点击一个按钮发送电子邮件。
这个按钮调用一个JavaScript函数，我在其中收集所有用户输入的数据，如from、to、subject、body，并希望将这些数据发送到我创建的一个Web服务，该服务将发送邮件。
我不想使用mailto，所以我选择了web服务。
问题是我无法发送数据：

$.ajax({
            type: 'POST',
            url: "Services/MailService.asmx/SendMail",
            dataType: "json",
            contentType: 'application/json; charset=utf-8',
            data: { 'loginName': "'" + loginName + "'", 'fromAddress': "'" + fromAddress + "'", 'toAddress': "'" + toAddress + "'", 'mailSubject': "'" + mailSubject + "'", 'mailBody': "'" + mailBody + "'"},
            success: function ()
            {
                alert("The email was sent successfully!");
            },
            error: function(data)
            {
                alert("An error occurred while trying to send the email. " + data.responseText);
            }
        });

我知道我在data属性中插入的内容是错误的。我已经尝试了以下方法，（一次一个）：

data: JSON.stringify({ 'loginName': loginName, 'fromAddress': fromAddress, 'toAddress': toAddress, 'mailSubject': mailSubject, 'mailBody': mailBody }),
data: { 'loginName': loginName, 'fromAddress': fromAddress, 'toAddress': toAddress, 'mailSubject': mailSubject, 'mailBody': mailBody },
data: { loginName: loginName, fromAddress: fromAddress, toAddress: toAddress, mailSubject: mailSubject, mailBody: mailBody },
data: "{ 'loginName': '" + loginName + "', 'fromAddress': '" + fromAddress + "', 'toAddress': '" + toAddress + "', 'maliSubject': '" + mailSubject + "', 'mailBody': '" + mailBody + "' }",

所有这些选项都会给予下列错误：

An error occurred while trying to send the email. {"Message":"Invalid web service call, missing value for parameter: \u0027mailBbody\u0027.","StackTrace":"   at System.Web.Script.Services.WebServiceMethodData.CallMethod(Object target, IDictionary`2 parameters)\r\n   at System.Web.Script.Services.RestHandler.InvokeMethod(HttpContext context, WebServiceMethodData methodData, IDictionary`2 rawParams)\r\n   at System.Web.Script.Services.RestHandler.ExecuteWebServiceCall(HttpContext context, WebServiceMethodData methodData)","ExceptionType":"System.InvalidOperationException"}

或

An error occurred while trying to send the email. {"Message":"Invalid JSON primitive: loginName.","StackTrace":"   at System.Web.Script.Serialization.JavaScriptObjectDeserializer.DeserializePrimitiveObject()\r\n   at System.Web.Script.Serialization.JavaScriptObjectDeserializer.DeserializeInternal(Int32 depth)\r\n   at System.Web.Script.Serialization.JavaScriptObjectDeserializer.BasicDeserialize(String input, Int32 depthLimit, JavaScriptSerializer serializer)\r\n   at System.Web.Script.Serialization.JavaScriptSerializer.Deserialize[T](String input)\r\n   at System.Web.Script.Services.RestHandler.ExecuteWebServiceCall(HttpContext context, WebServiceMethodData methodData)","ExceptionType":"System.ArgumentException"}

我不知道我做错了什么。
Web服务如下所示：

[System.Web.Script.Services.ScriptService]
public class WebService1 : System.Web.Services.WebService
{
    [WebMethod]
    public void SendMail(string loginName, string fromAddress, string toAddress, string mailSubject, string mailBody)
    {
        MailMessage mailMsg = new MailMessage(fromAddress, toAddress);
        mailMsg.Subject = mailSubject;
        mailMsg.Body = mailBody;

        string pathToCreate = "~/Upload/" + loginName + "/";
        if (Directory.Exists(Server.MapPath(pathToCreate)))
        {
            if (Directory.GetFiles(Server.MapPath(pathToCreate)).Length > 0)
            {
                string[] attachedFiles = Directory.GetFiles(Server.MapPath(pathToCreate));
                foreach (string a in attachedFiles)
                {
                    Attachment data = new Attachment(a);
                    mailMsg.Attachments.Add(data);
                }
            }
        }

        SmtpClient smtp = new SmtpClient();
        smtp.Send(mailMsg);
    }
}

我可以做些什么来解决这个问题？