diff --git a/pmcalendar.php b/pmcalendar.php
index 3f8fd0c..826da47 100644
--- a/pmcalendar.php
+++ b/pmcalendar.php
@@ -205,8 +205,9 @@ if ($act == 'newevent') {
     $del = r('del');
     $content = stripslashes(r('content'));
     $dict = array();
-    $event = DB::getone("select yanqi_history from calendar where id={$id}");
+    $event = DB::getone("select yanqi_history from calendar where id='{$id}'");
     $yanqi_history = $event['yanqi_history'];
+    $yanqi_history=json_decode($yanqi_history,true);
     if(!$del) {
         $yanqi_history[$idx]['reason'] = $content;
     }