I am receiving json form when submitting a contact form , and I would like to get the inline message of it ;
xhr.onreadystatechange = function() {
            if(xhr.readyState == 4 && xhr.status == 200) { 
               setFormMessage(xhr.responseText.) // Returns a 200 response if the submission is successful.
            } else if (xhr.readyState == 4 && xhr.status == 400){ 
                setFormMessage(xhr.responseTex)); // Returns a 400 error the submission is rejected.          
            } else if (xhr.readyState == 4 && xhr.status == 403){ 
                setFormMessage(xhr.responseText); // Returns a 403 error if the portal isn't allowed to post submissions.           
            } else if (xhr.readyState == 4 && xhr.status == 404){ 
                setFormMessage(xhr.responseText); //Returns a 404 error if the formGuid isn't found     
            }
           }
this the message when it's 200 :
{"inlineMessage":"Thanks for submitting the form."}
I have already tried to get the value of the inlineMessage like this :
xhr.responseText.inlineMessage 
but it didn't work ! any idea how to get that message
 
     
    