Post method with multiple parameter - asp.net-mvc

Question

I am unable to insert multiple rows in database using Post method in MVC web API. I have written code for it but when i am testing by inserting multiple rows through postman it is giving error. At line first the variable "delegatetable" shows null due to which error is coming. i am not doing database connection through entity framework, i have created a DelegateTable class.
public HttpResponseMessage Post(List<DelegateTable> delegatetable)
{
try
{
using (var delegateContext = new ShowContext())
{
foreach (DelegateTable item in delegatetable)
{
DelegateTable delegates = new DelegateTable();
delegates.Salutation__c = item.Salutation__c;
delegates.First_Name__c = item.First_Name__c;
delegates.Last_Name__c = item.Last_Name__c;
delegates.Account_Name__c = item.Account_Name__c;
delegates.Contact_Email__c = item.Contact_Email__c;
delegates.Category__c = item.Category__c;
delegates.Conference_Type__c = item.Conference_Type__c;
delegates.Conference_Selection__c = item.Conference_Selection__c;
delegates.Payment_Statuss__c = item.Payment_Statuss__c;
delegates.Barcode__c = item.Barcode__c;
delegateContext.SaveChanges();
}
var message = Request.CreateResponse(HttpStatusCode.Created, delegatetable);
message.Headers.Location = new Uri(Request.RequestUri.ToString());
return message;
}
}
catch (Exception ex)
{
return Request.CreateErrorResponse(HttpStatusCode.BadRequest, ex);
}
}
Json data that i am passing is below
[
{
"attributes": {
"type": "Registration__c",
"url": "/services/data/v43.0/sobjects/Registration__c/a3h8E0000009VuVQAU"
},
"Salutation__c": "Dr.",
"First_Name__c": "Test",
"Last_Name__c": "Test",
"Account_Name__c": "Test",
"Contact_Email__c": "test123#gmail.com",
"Category__c": "Test",
"Conference_Type__c": null,
"Conference_Selection__c": null,
"Payment_Statuss__c": null,
"Barcode__c": "Test"
},
{
"attributes": {
"type": "Registration__c",
"url": "/services/data/v43.0/sobjects/Registration__c/a3hD0000001kEfOIAU"
},
"Salutation__c": "Mr.",
"First_Name__c": "Demo",
"Last_Name__c": "Demo",
"Account_Name__c": "Demo",
"Contact_Email__c": "Demo#gmail.com",
"Category__c": "Demo",
"Conference_Type__c": null,
"Conference_Selection__c": null,
"Payment_Statuss__c": null,
"Barcode__c": null
}
]

Answer 1

You may try to reformat your payload as a JSON array, as the problem might be that the payload cannot be converted to a List.
Try this:
{
"delegates" :
[
{
"attributes": ..., ...
},
{ "attributes": ..., ...
},
...
]
}