If you have an issue logging into your Twilio SendGrid account, please read this document. For any questions regarding login issues, please contact our support team.
If you have a non-library Twilio SendGrid issue, please contact our support team.
- Continue Using the v2 API
- Environment Variables and Your Twilio SendGrid API Key
- Error Messages
- Migrating from the v2 API to v3
- Migrating from the v8 SDK to v9
- Missing Classes
- Testing v3 /mail/send Calls Directly
- Using .NET 4.5.1 and lower
- Using the Package Manager
- Versioning Convention
- Viewing the Request Body
- UI requests are failing
- Verifying Event Webhooks
Here is the last working version with v2 support.
Using Nuget:
PM> Install-Package Sendgrid -Version 6.3.4
Download:
Click the "Clone or download" green button in GitHub and choose download.
All of our examples assume you are using environment variables to hold your Twilio SendGrid API key.
If you choose to add your Twilio SendGrid API key directly (not recommended):
string apiKey = Environment.GetEnvironmentVariable("SENDGRID_API_KEY");
becomes
string apiKey = "SENDGRID_API_KEY";
In the first case, SENDGRID_API_KEY is in reference to the name of the environment variable, while the second case references the actual Twilio SendGrid API Key.
By default if the API returns an error, it doesn't throw an exception, but you can read the error message returned by Twilio SendGrid's API:
var response = await client.RequestAsync(method: SendGridClient.Method.POST,
requestBody: msg.Serialize(),
urlPath: "mail/send");
Console.WriteLine(response.StatusCode);
Console.WriteLine(response.Body.ReadAsStringAsync().Result); // The message will be here
Console.WriteLine(response.Headers.ToString());
If you want to throw the exception when the API returns an error, init the SendGridClient with options including 'HttpErrorAsException' as true:
var client = new SendGridClient(new SendGridClientOptions{ ApiKey = apiKey, HttpErrorAsException = true });
Then if an error is thrown due to a failed request, a summary of that error along with a link to the appropriate place in the documentation will be sent back as a JSON object in the Exception Message. You can also deserialize the JSON object as a SendGridErrorResponse. Every error status code returned by the API has its own type of exception (BadRequestException, UnauthorizedException, PayloadTooLargeException, SendGridInternalException, etc.). All the possibles status codes and errors are documented here.
var client = new SendGridClient(new SendGridClientOptions{ ApiKey = "SG.12345678901234567890123456789012", HttpErrorAsException = true });
try
{
var response = await client.RequestAsync(method: SendGridClient.Method.POST,
requestBody: msg.Serialize(),
urlPath: "mail/send");
}
catch(Exception ex)
{
SendGridErrorResponse errorResponse = JsonConvert.DeserializeObject<SendGridErrorResponse>(ex.Message);
Console.WriteLine(ex.Message);
//{
// "ErrorHttpStatusCode":401,
// "ErrorReasonPhrase":"Unauthorized",
// "SendGridErrorMessage":"Permission denied, wrong credentials",
// "FieldWithError":null,
// "HelpLink":null
//}
}
var client = new SendGridClient(new SendGridClientOptions{ ApiKey = apiKey, HttpErrorAsException = true });
try
{
var from = new EmailAddress("", "Example User"); // From email null
var msg = MailHelper.CreateSingleEmail(from, to, subject, plainTextContent, htmlContent);
var response = await client.SendEmailAsync(msg).ConfigureAwait(false);
}
catch (Exception ex)
{
SendGridErrorResponse errorResponse = JsonConvert.DeserializeObject<SendGridErrorResponse>(ex.Message);
Console.WriteLine(ex.Message);
//{
// "ErrorHttpStatusCode":400,
// "ErrorReasonPhrase":"Bad Request",
// "SendGridErrorMessage":"The from email does not contain a valid address.",
// "FieldWithError":"from.email",
// "HelpLink":"http://sendgrid.com/docs/API_Reference/Web_API_v3/Mail/errors.html#message.from"
//}
}
Please review our guide on how to migrate from v2 to v3.
v9 of this SDK is a complete rewrite that includes the removal of dynamic dependencies, a new Mail Helper and support for .NET Standard 1.3.
Please begin at the README.
If you receive one of the following errors, or something similar:
- ‘Helpers’ does not exist in the namespace ‘SengrGrid’
- The type or namespace name ‘Mail’ could not be found
it means that you are probably not compiling your application to .NET 4.5.2. Currently, this is the only supported version of .NET by Twilio SendGrid.
The current solution is to download the code directly into your project and change the compile target to the desired version.
Here are some cURL examples for common use cases.
Microsoft is no longer supporting these versions. We strongly advise upgrading your software to target .NET 4.5.2 or higher. If you are unable to do so, the current solution is to download the code directly into your project and change the compile target to the desired version.
We upload this library to Nuget whenever we make a release. This allows you to use Nuget for easy installation.
In most cases we recommend you download the latest version of the library, but if you need a different version, please use:
PM> Install-Package Sendgrid -Version X.X.X
We follow the MAJOR.MINOR.PATCH versioning scheme as described by SemVer.org. Therefore, we recommend that you always pin (or vendor) the particular version you are working with your code and never auto-update to the latest version. Especially when there is a MAJOR point release since that is guaranteed to be a breaking change. Changes are documented in the CHANGELOG and releases section.
When debugging or testing, it may be useful to examine the raw request body to compare against the documented format.
You can do this right before you call var response = await client.SendEmailAsync(msg);
like so:
Console.WriteLine(msg.Serialize());
If your UI based requests are failing, it may be due to a little known issue where the UI only has a single thread. The answer here is to use ConfigureAwait(false)
on the end of your request call so that the thread does not reset back to request context and stays in capture context. Normally, async the request thread would "let go" of the capture context and reset to request context. With the UI, there is only a single thread, so you have to force the thread to switch to capture context, using ConfigureAwait(false)
. For more information, please see a better summary that is linked to a longer article in StackOverflow.
In our example code, you would change:
var response = await client.SendEmailAsync(msg);
to
var response = await client.SendEmailAsync(msg).ConfigureAwait(false);
If you are running a newer versions of .NET you can turn on a couple different Roslyn based analyzers that will trigger build errors if you're not calling .ConfigureAwait(false)
on your async methods.
Roslynator.Analyzers
can be installed through NuGet or as a VS plugin, but if you use the plugin then the analyzers won't run on build servers and trigger build errors as the NuGet package would. (thanks to xt0rted for this tip!)
Twilio SendGrid's Event Webhook will notify a URL via HTTP POST with information about events that occur as your mail is processed. This article covers all you need to know to secure the Event Webhook, allowing you to verify that incoming requests originate from Twilio SendGrid. The sendgrid-csharp library can help you verify these Signed Event Webhooks.
You can find the end-to-end usage example and the tests here. If you are still having trouble getting the validation to work, follow the following instructions:
- Be sure to use the raw payload for validation
- Be sure to include a trailing carriage return and newline in your payload
- In case of multi-event webhooks, make sure you include the trailing newline and carriage return after each event