单图表单图片上传限制

src/Form/Field/Image.php

@@ -66,6 +66,7 @@ class Image extends File
             $this->options['accept'] = [];
         }
 
+        $this->options['fileNumLimit'] = 1;
         $this->options['accept']['mimeTypes'] = 'image/*';
         $this->options['isImage'] = true;
     }