Preview Image and Upload Image, What File Reader function to use?









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I want to upload multiple files to my asp.net core server but first I want to preview them.



I found many examples using 



 reader.readAsDataURL(incomingFile);


then later I just extract out: evt.target.result



but my understanding is this creates a url that is in a sense temporary. What method should I use if I want to upload the raw bytes to my server but also still do a image preview before uploading?



I see



readAsArrayBuffer() 
readAsBinaryString() // what seems to be deprecated.





javascript html file







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    up vote
    0
    down vote

    favorite












    I want to upload multiple files to my asp.net core server but first I want to preview them.



    I found many examples using 



     reader.readAsDataURL(incomingFile);


    then later I just extract out: evt.target.result



    but my understanding is this creates a url that is in a sense temporary. What method should I use if I want to upload the raw bytes to my server but also still do a image preview before uploading?



    I see



    readAsArrayBuffer() 
    readAsBinaryString() // what seems to be deprecated.





    javascript html file







    share|improve this question























      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      I want to upload multiple files to my asp.net core server but first I want to preview them.



      I found many examples using 



       reader.readAsDataURL(incomingFile);


      then later I just extract out: evt.target.result



      but my understanding is this creates a url that is in a sense temporary. What method should I use if I want to upload the raw bytes to my server but also still do a image preview before uploading?



      I see



      readAsArrayBuffer() 
      readAsBinaryString() // what seems to be deprecated.





      javascript html file







      share|improve this question













      I want to upload multiple files to my asp.net core server but first I want to preview them.



      I found many examples using 



       reader.readAsDataURL(incomingFile);


      then later I just extract out: evt.target.result



      but my understanding is this creates a url that is in a sense temporary. What method should I use if I want to upload the raw bytes to my server but also still do a image preview before uploading?



      I see



      readAsArrayBuffer() 
      readAsBinaryString() // what seems to be deprecated.





      javascript html file




      javascript html file






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 9 at 18:00









      chobo2

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