how do i fix "cannot read property match of undefned" in this code

i'm trying to integrate nativescript-imagepicker plugin with my Nativescript App, but i get error **cannot read **property match of undefined**** below is what i have already tried, thanks.

function onSelectSingleTap(args) {  
    var context = imagepickerModule.create({
        mode: "single"
    });
    if (platformModule.device.os === "Android" && platformModule.device.sdkVersion >= 23) {   
        permissions.requestPermission(android.Manifest.permission.READ_EXTERNAL_STORAGE, "I need these permissions to read from storage")
        .then(function() {
            console.log("Permissions granted!");
            startSelection(context);
        })
        .catch(function() {
            console.log("Uh oh, no permissions - plan B time!");
        });
    } else {
        startSelection(context);
    }
}

function sendImages(selected) {
    let fileUri = selected.fileUri;
    imageName = extractImageName(fileUri);

    var request = {
        url: "http://vvvvvv.com/skog/upload.php",
        method: "POST",
        headers: {
            "Content-Type": "application/octet-stream",
            "File-Name": imageName
        },
        description: "{ 'uploading': " + imageName + " }"
    };
    //get the image source and upload from there
    selected.getImage().then(imageSource => {
        let temp = fs.knownFolders.temp();
        let uniqueName = '_' + Math.random().toString(36).substr(2, 9);
        let filePath = fs.path.join(temp.path, uniqueName + ".jpg");
        let saved = imageSource.saveToFile(filePath, enums.ImageFormat.jpeg);
        console.log(`item saved:${saved}`);
        var task = session.uploadFile(filePath, request);

        task.on("progress", logEvent);
        task.on("error", logEvent);
        task.on("complete", x => cleanFile(filePath));
    });
    //return task;
}
function logEvent(e) {      
        console.log("----------------");
        console.log('Status: ' + e.eventName);
        console.log('Error: ' + e.error);
        // console.log(e.object);
        if (e.totalBytes !== undefined) {
            console.log('current bytes transfered: ' + e.currentBytes);
            console.log('Total bytes to transfer: ' + e.totalBytes);
        }  
    }
function cleanFile(file){
    fs.remove(file);
}
function startSelection(context) {
    context
        .authorize()
        .then(function() {
            imageItems.length = 0;
            return context.present();
        })
        .then(function(selection) {
            selection.forEach(function(selected) {
                sendImages(selected);
                //selected.uploadTask = sendImages(selected);             
                selected.imageName = imageName;

                console.log("----------------");
                console.log("uri: " + selected.uri);           
                console.log("fileUri: " + selected.fileUri);
                console.log('Image name:' + imageName);

                imageItems.push(selected);
            });
            //list.items = selection;
        }).catch(function (e) {
      console.log(e);
      alert(e.message);
        });
}
function extractImageName(fileUri) {
  var pattern = /[^/]*$/;
  var imageName = fileUri.match(pattern);

  return imageName[0];
}

I don't think the fault is from the php which is why i'm not adding the code to the question, but if you think otherwise, please let me know please help

this will do it

function onSelectSingleTap(args) {
      var context = imagepickerModule.create({
          mode: "single"
      });

      if (platformModule.device.os === "Android" && platformModule.device.sdkVersion >= 23) {
          permissions.requestPermission(android.Manifest.permission.READ_EXTERNAL_STORAGE, "I need these permissions to read from storage")
              .then(function () {
                  console.log("Permissions granted!");
                  startSelection(context);
              })
              .catch(function () {
                  console.log("Uh oh, no permissions - plan B time!");
              });
      } else {
          startSelection(context);
      }
    }


    function startSelection(context) {

      context
          .authorize()
          .then(function () {

              return context.present();
          })
          .then(function (selection) {
            selection.forEach(function(selected) {
              //alert(selected.android.toString()); 
              var file =  selected.android.toString();
              var url = "https://adekunletestprojects.000webhostapp.com/skog/upload.php";
              var name = file.substr(file.lastIndexOf("/") + 1);
              //alert(name);
              var bghttp = require("nativescript-background-http");
              var session = bghttp.session("image-upload");
              var request = {
              url: url,
              method: "POST",
              headers: {
                  "Content-Type": "application/octet-stream",
                  "File-Name": name
              },
            description: "Uploading " + name
        };

            var task = session.uploadFile(file, request);
            task.on("progress", progressHandler);
            return task;
            function progressHandler(e) {
              var toast = Toast.makeText("uploaded " + e.currentBytes + " / " + e.totalBytes);
              toast.show();
          }
            });
          }).catch(function (e) {
              console.log(e.eventName);
              alert(e.message);
          });
    }