Sendgrid dynamic data not being sent to Template

Question

This is how I send my email:

public async System.Threading.Tasks.Task<string> SendInternalEmail(BasicEmailStructureViewModel Structure, List<string> AdditionalVariables, TenantEmailTemplate tenantEmailTemplate, TenantCommunication tenantCommunication, string ReceiverId, string ReceiverEmail, string ReceiverName, string CampaignName)
{
    try
    {

        var client = new SendGridClient(tenantCommunication.SendgridApiKey);
        var message = new SendGridMessage();
        message.SetFrom(new EmailAddress(tenantCommunication.SendgridPrimarySender, tenantCommunication.SendgridPrimarySenderTag));
        message.AddTo(new EmailAddress(ReceiverEmail, $"{ReceiverName}"));
        message.Subject = tenantEmailTemplate.Subject;
        message.SetTemplateId(tenantEmailTemplate.TemplateId);
        List<string> jsonVars = new List<string>();

        var subjectString = @$"""subject"":""{tenantEmailTemplate.Subject}""";

        jsonVars.Add(subjectString);

        foreach (PropertyInfo prop in Structure.GetType().GetProperties())
        {
            var variableString = @$"""{prop.Name}"":""{prop.GetValue(Structure, null)}""";
        }

        for (var i = 0; i < AdditionalVariables.Count; i++)
        {
            jsonVars.Add(AdditionalVariables[i]);
        }
        var flattenList = "{" + string.Join(",", jsonVars) + "}";
        var emailData = Newtonsoft.Json.JsonConvert.DeserializeObject<object>(flattenList);
        message.SetTemplateData(emailData);
        if (CampaignName != null && CampaignName != "")
        {
            message.AddCustomArg("CampaignName", CampaignName);
        }
        var response = await client.SendEmailAsync(message);
        if (response.IsSuccessStatusCode == true)
        {
            return Guid.NewGuid().ToString();
        }
        else
        {
            var errorMessage = response.Body.ReadAsStringAsync().Result;
            return errorMessage;
        }
    }
    catch(Exception e)
    {
        if (e != null)
        {
            return e.Message;
        }
    }
    return "Invalid Email";
}

A typical input to this function will be like this:

var variableString = @$"""verification_link"":""www.website.com?Key={Input.Key}""";

My email sends normally, however, none of the variables that I have set have been sent through. This is based roughly off the template sample on github: https://github.com/sendgrid/sendgrid-csharp/blob/main/examples/templates/templates.cs

Is there another sample I can use or what is the correct way to send variables dynamically?

Answer 1

I don't think that is the best way to construct the JSON for your dynamic template variables.

Would it be possible for you to build the variables as an object and then serialize them. Like:

var templateData = new {
  subject = tenantEmailTemplate.Subjectm
  otherVariableName = otherVariable
};

string emailData = JsonConvert.SerializeObject(templateData);
message.SetTemplateData(emailData);