I came across this function to convert arraybuffer to base64 string which is working fine for first time when i upload around 700MB file. Again I tried to upload 150MB file, browser is giving 'Out Of Memory' exception.

Method used to convert array buffer to base 64 string. Please let me know if there is there is size limitation for window.btoa() or is it broswer cache issue.

  function _arrayBufferToBase64( buffer ) {
        var binary = '';
        var bytes = new Uint8Array( buffer );
        var len = bytes.byteLength;
        for (var i = 0; i < len; i++) {
            binary += String.fromCharCode( bytes[ i ] );
        }
        return window.btoa( binary );
    }

I am calling the above method in Filereader to read file.

 private ProcessReadFile(file:File){
   return new Promise<void>(resolve=>{
        const reader= new FileReader();
        let content:any;
        reader.onloadend=()=>{
                     content=reader.result;
                     var fileContent=_arrayBufferToBase64(content);
                    this.fileUpload.push({
                       Filecontent:fileContent;
                       FileType:file.Type
                     });
                 resolve;
         };
     });
  }

I tried with "_arrayBufferToBase64" method and first time its uploading fine for 600MB and again i tried to upload 150MB file, browser is throwing "out of memory" page. Please let me now how can we avoid this or is there any limit to size or above method is storing in browser cache.

Please suggest