[代码优化](v2.6)：fix bug

close https://github.com/elunez/eladmin/issues/504

src/utils/permission.js

@@ -5,21 +5,25 @@ import store from '@/store'
  * @returns {Boolean}
  * @example see @/views/permission/directive.vue
  */
-export default function checkPermission(value) {
-  if (value && value instanceof Array && value.length > 0) {
-    const roles = store.getters && store.getters.roles
-    const permissionRoles = value
+export default {
+  install(Vue) {
+    Vue.prototype.checkPer = (value) => {
+      if (value && value instanceof Array && value.length > 0) {
+        const roles = store.getters && store.getters.roles
+        const permissionRoles = value
 
-    const hasPermission = roles.some(role => {
-      return permissionRoles.includes(role)
-    })
+        const hasPermission = roles.some(role => {
+          return permissionRoles.includes(role)
+        })
 
-    if (!hasPermission) {
-      return false
+        if (!hasPermission) {
+          return false
+        }
+        return true
+      } else {
+        console.error(`need roles! Like v-permission="['admin','editor']"`)
+        return false
+      }
     }
-    return true
-  } else {
-    console.error(`need roles! Like v-permission="['admin','editor']"`)
-    return false
   }
 }