Converting an image to base64 in angular 2

Question

Converting an image to base64 in angular 2, image is uploaded from local . Current am using fileLoadedEvent.target.result. The problem is, when I send this base64 string through REST services to java, it is not able to decode it. When i try this base64 string with free online encoder-decoder, there also I cannot see decoded image. I tried using canvas also. Am not getting proper result. One thing is sure the base64 string what am getting is not proper one, do I need to add any package for this ? Or in angular 2 is there any perticular way to encode the image to base64 as it was there in angular 1 - angular-base64-upload package.

Pls find below my sample code

onFileChangeEncodeImageFileAsURL(event:any,imgLogoUpload:any,imageForLogo:any,imageDiv:any)
{
    var filesSelected = imgLogoUpload.files;
    var self = this;
    if (filesSelected.length > 0) {
      var fileToLoad = filesSelected[0]; 

      //Reading Image file, encode and display
       var  reader: FileReader = new FileReader();
       reader.onloadend = function(fileLoadedEvent:any) {

       //SECOND METHO
       var imgSrcData = fileLoadedEvent.target.result; // <--- data: base64 

        var newImage = imageForLogo;
        newImage.src = imgSrcData;
        imageDiv.innerHTML = newImage.outerHTML;

      }
      reader.readAsDataURL(fileToLoad);
    }
}

Answer 1

Working plunkr for base64 String

https://plnkr.co/edit/PFfebmnqH0eQR9I92v0G?p=preview

  handleFileSelect(evt){
      var files = evt.target.files;
      var file = files[0];

    if (files && file) {
        var reader = new FileReader();

        reader.onload =this._handleReaderLoaded.bind(this);

        reader.readAsBinaryString(file);
    }
  }



  _handleReaderLoaded(readerEvt) {
     var binaryString = readerEvt.target.result;
            this.base64textString= btoa(binaryString);
            console.log(btoa(binaryString));
    }

Answer 2

I modified Parth Ghiya answer a bit, so you can upload 1- many images, and they are all stored in an array as base64 encoded strings

base64textString = [];

onUploadChange(evt: any) {
  const file = evt.target.files[0];

  if (file) {
    const reader = new FileReader();

    reader.onload = this.handleReaderLoaded.bind(this);
    reader.readAsBinaryString(file);
  }
}

handleReaderLoaded(e) {
  this.base64textString.push('data:image/png;base64,' + btoa(e.target.result));
}

HTML file

<input type="file" (change)="onUploadChange($event)" accept=".png, .jpg, .jpeg, .pdf" />
<img *ngFor="let item of base64textString"  src={{item}} alt="" id="img">