sp.utilities.utility.sendemail + how to send email to multiple users

Question

Below is my code to send email through SharePoint (2016 OnPrem)

function sendEmail(from, to,subject,body) {
//Get the relative url of the site
var siteurl = _spPageContextInfo.webServerRelativeUrl;
var urlTemplate = siteurl + "/_api/SP.Utilities.Utility.SendEmail";
$.ajax({
    contentType: 'application/json',
    url: urlTemplate,
    type: "POST",
    data: JSON.stringify({
        'properties': {
            '__metadata': {
                'type': 'SP.Utilities.EmailProperties'
            },
            'From': from,
            'To': {
                'results': [to]
            },
            'Body': body,
            'Subject': subject
        }
    }),
    headers: {
        "Accept": "application/json;odata=verbose",
        "content-type": "application/json;odata=verbose",
        "X-RequestDigest": jQuery("#__REQUESTDIGEST").val()
    },
    success: function(data) {
        //alert('Email Sent Successfully');
        var isSent = true;
    },
    error: function(err) {

        alert('Error in sending Email to System Admin: ' + JSON.stringify(err));

    }
});

}

and below is my calling statement;

sendEmail("abc@def.com","a@b.com,b@b.com","Test Subject","Test Body");

Email gets sent when there is 1 user. However when trying with multiple users getting error

Error in sending Email to System Admin: {"readyState":4,"responseText":"{\"error\":{\"code\":\"-2130242040, Microsoft.SharePoint.SPException\",\"message\":{\"lang\":\"en-US\",\"value\":\"The e-mail message cannot be sent. Make sure the e-mail has a valid recipient.\"}}}","responseJSON":{"error":{"code":"-2130242040, Microsoft.SharePoint.SPException","message":{"lang":"en-US","value":"The e-mail message cannot be sent. Make sure the e-mail has a valid recipient."}}},"status":400,"statusText":"Bad Request"}

Kindly let know how to put multiple users in TO. Tried with ; seperated email addresses. However same error.

Thank you

Answer 1

The format of your "To" variable must be an Array witch contains emails (or domain\login). Here, you pass a string witch contains email separated by comma.

Try somthing like :

var recipients = ["a@b.com","b@b.com"];
sendEmail("abc@def.com",recipients ,"Test Subject","Test Body");

And change the "data" in your query like :

data: JSON.stringify({
        'properties': {
            '__metadata': {
                'type': 'SP.Utilities.EmailProperties'
            },
            'From': from,
            'To': {
                'results': to
            },
            'Body': body,
            'Subject': subject
        }
    })

Like kasper said, your recipent must be a SharePoint site users. (And the From too) You can't send Email from sharepoint to other email who are not in your organisation

check this link for an exemple : SharePoint 2013: REST API/Client Code to send mails