I have a webpage where I drop the zip file which extracts the files. how to get the file and use it as img src. I'm getting 'undefined' imgurl1 value

    let url1 = "IM/" + DIALOG_BACKGROUND_IMAGE ;
        try {
              JSZip.loadAsync(newFile).then(function (zip) {
                   for (var name in zip.files) {
                       if (name === url1) {
                           return  zipFiles.file(name).async('blob');
                       }
                   }
              return zip.file("").async("string");
              }).then(function success(blob) {
                    const reader = new FileReader();
                    reader.readAsDataURL(blob); 
                    reader.onloadend = function() {
                    imgurl1 = reader.result;     
                 }
                 puttingData(data, imgurl1,imgurl1);                    
             }, function error(e) {
                    console.log(e);
                 });
                } catch (e) {
                    console.log(e);
                }