How to post string array using POSTMAN?

Question

I am using Postman to send an array of string to a web API. The web API method looks like:

[HttpPost]
public async Task<IEnumerable<DocumentDTO>> GetDocuments([FromBody]IEnumerable<string> documentNames)
{
    return await _service.GetDocuments(documentNames);
}

I saw this SO post on how to send an array using Postman. Here is how I am sending the array:

Fiddler shows the request's content type is multipart/form-data;

But I am getting an error response:

{ "Message": "The request entity's media type 'multipart/form-data' is not supported for this resource.", "ExceptionMessage": "No MediaTypeFormatter is available to read an object of type 'IEnumerable1' from content with media type 'multipart/form-data'.", "ExceptionType": "System.Net.Http.UnsupportedMediaTypeException", "StackTrace": " at System.Net.Http.HttpContentExtensions.ReadAsAsync[T](HttpContent content, Type type, IEnumerable1 formatters, IFormatterLogger formatterLogger, CancellationToken cancellationToken)\r\n at System.Web.Http.ModelBinding.FormatterParameterBinding.ReadContentAsync(HttpRequestMessage request, Type type, IEnumerable`1 formatters, IFormatterLogger formatterLogger, CancellationToken cancellationToken)" }

I have tried setting the key as documentNames,documentNames[], documentNames[0].

I have tried selecting the body as x-www-form-urlencoded. When I do that, the API receives an empty collection.

I have tried selecting a body as raw. When I do that, the API receives null as a parameter.

Questions

How do I send a string array using form-data?
How do I send a string array using x-www-form-urlencoded?
How do I send a string array as raw JSON?

score 27 · Answer 1 · answered Sep 23 '16 at 18:37

27

Pass it as JSON array and select the raw option like below

For a API method signature

    public void Post([FromBody] IEnumerable<string> value)
    {
      //some processing
    }

answered Sep 23 '16 at 18:37

Rahul

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Thank you , I used same idea for list of complex objects and it works fine for me – Omar Isaid Sep 19 '19 at 10:36
so simple and I was fiddling with it for such a long time. it came to my surprise that passing it as { value:[1,2,3] } cannot be recognized by the request handler. – Ben Dec 04 '19 at 17:11

WasiF · Answer 2 · 2021-04-15T07:21:38.787

19

if you want to initialize an array via params, you can do that.

use a `variable` with a same name

edited Apr 15 '21 at 07:21

answered Nov 08 '18 at 12:08

WasiF

26,101
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128

This is not working. – Anmol Jain Mar 15 '22 at 05:31
@AnmolJain This worked for me and many others. Please check your code. In case you find better way than this, post a comment and I'll update the answer. – WasiF Mar 15 '22 at 06:01

score 7 · Answer 3 · answered Jun 29 '21 at 02:55

7

Use same key in form remember add [] on it

answered Jun 29 '21 at 02:55

Hà Mã Tím

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2
3

adding[] works, specially when we json_encode to save it as a string in our database. if you do `categories[0]` / `categories[1]` it will create key value pairs and the value arriving at the server will not be in a single array – Manas Jan 19 '22 at 04:53

How to post string array using POSTMAN?

3 Answers3

use a variable with a same name

use a `variable` with a same name