On folder/files drop validate file extension

Author: Jasmin

src/ngx-file-drop/ngx-file-drop.component.ts

@@ -235,7 +235,7 @@ export class NgxFileDropComponent implements OnDestroy {
   private traverseFileTree(item: FileSystemEntry, path: string): void {
     if (item.isFile) {
       const toUpload: NgxFileDropEntry = new NgxFileDropEntry(path, item);
-      this.files.push(toUpload);
+      this.addToQueue(toUpload);
 
     } else {
       path = path + '/';
@@ -332,9 +332,28 @@ export class NgxFileDropComponent implements OnDestroy {
   }
 
   private addToQueue(item: NgxFileDropEntry): void {
+    const isAcceptedExt = this.isAcceptedExtension(this.accept, item.fileEntry.name);
+    if (!isAcceptedExt) return;
+
     this.files.push(item);
   }
 
+  private getFileExtension(fileName: string) {
+    const extension = fileName.split('.').slice(-1)[0];
+    return `.${extension}`;
+  }
+
+  private isAcceptedExtension(acceptedExtensions: string, fileName: string) {
+    if (acceptedExtensions === "*") {
+      return true;
+    }
+
+    const fileExtension = this.getFileExtension(fileName);
+
+    const acceptedExtList = acceptedExtensions.split(',');
+    return acceptedExtList.includes(fileExtension);
+  }
+
   private preventAndStop(event: Event): void {
     event.stopPropagation();
     event.preventDefault();