[WHAT] 修正API回傳值判斷

FrontEnd/pages/exhibition/_id.vue

@@ -397,7 +397,7 @@ export default {
         )
         .then((result) => {
 
-          if (result.data.DATA.rel) {
+          if (result && result.data && result.data.DATA && result.data.DATA.rel) {
 
             let exhib = result.data.DATA.rel;
             this.exhibition.id = exhib.ExhibitionID;