Multiple Image upload with Data ionic 2

I want to upload multiple image with form data. I tried with

fileKey: "attached_file1",
            fileName: filename,
            chunkedMode: false,
            mimeType: "multipart/form-data",
 params: {'token':  etc.....}

but with this i am able to send only 1 data at single time. so i can’t use looping here ,

and when i am trying with some post method with form data then it is not working so can anyone let me know the correct method to do this ?

can you share your code here. also i want to upload multiple images to the server