abstrak：<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>偵聽器</title> </head> <body&g
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>偵聽器</title>
</head>
<body>
<div id="box">
用戶名:<input type="text" v-model="username"> <br>
<h3>{{length}}</h3>
<h3 v-show="isShow" :style="warning">{{message}}</h3>
</div>
<script src="js/vue.js"></script>
<script>
new Vue({
el: '#box',
data: {
username: '',
length: 0,
message: '用戶名過短',
isShow: false,
warning: 'color:red'
},
watch: {
username: function () {
this.length=this.username.length;
//console.log(this.username);
if (this.length < 6) {
this.isShow = true;
} else {
this.isShow = false;
}
}
}
});
</script>
</body>
</html>偵聽器:實(shí)時監(jiān)測頁面中數(shù)據(jù)的變化
實(shí)時更新數(shù)據(jù)模型中的屬性,并完成指定的動作
watch中偵聽的屬性必須是頁面中的變量
Guru membetulkan：滅絕師太Masa pembetulan：2018-11-26 10:32:18
Rumusan guru：學(xué)習(xí)的進(jìn)度很快，學(xué)習(xí)的過程中要確保知識點(diǎn)掌握奧！