FIX v-time指令没有更新

src/directives/time.js

@@ -59,9 +59,11 @@ var Time = {
 	}
 }
 
-export default {
+export default (el, binding) => {
-	mounted(el, binding) {
 	let { value, modifiers} = binding
+	if(!value){
+		return false
+	}
 	if(value.toString().length == 10){
 		value = value * 1000
 	}
@@ -74,5 +76,4 @@ export default {
 		const format = el.getAttribute('format') || undefined
 		el.innerHTML = tool.dateFormat(value, format)
 	}
-	}
+}
-};