修复账单如果没有附件则现实错误页面的问题

application/em/view/invoice/detail.html

@@ -121,7 +121,7 @@
                                         <span class="x-red">*</span>抄表单照片
                                     </label>
                                     <div class="layui-input-inline">
-                                        {if $inv.useage.photo.src == ''}
+                                        {if !isset($inv.useage.photo.src) ||  $inv.useage.photo.src == ''}
                                             <input type="text"
                                                autocomplete="off" class="layui-input layui-no-border" value="未上传抄表照片" disabled="disabled">
                                         {else /}