computed \ methods  裏邊是（各種）函數，函數裏邊調用變量用this. 

computed 裏邊是 （各種）函數返回對象

實例中data是對象, 在組件中（在其他裏邊）data是函數返回對象

push() 方法可向數組的末尾添加一個或多個元素，並返回新的長度。

v-model:把當前這個input裏邊的值指到哪裏

<input v-model="current.title" id="task-input" type="text">

JSON.stringify() 方法將 JavaScript對象 轉換為 JSON字符串。

JSON.parse() 方法將 JSON字符串 轉換為 JavaScript對象。

<p id="demo"></p>

<script>

var obj = { "name":"runoob", "alexa":10000, "site":"www.runoob.com"};
var myJSON = JSON.stringify(obj);
document.getElementById("demo").innerHTML = myJSON;

</script>

//運行結果：{"name":"runoob","alexa":10000,"site":"www.runoob.com"}

<p id="demo"></p>
<script>
var
 
 text = ‘{"employees":[‘ +
‘{"name":"菜鳥教程","site":"http://www.runoob.com" },‘ +
‘{"name":"Google","site":"http://www.Google.com" },‘ +
‘{"name":"Taobao","site":"http://www.taobao.com" }]}‘;
obj = JSON.parse(text);
document.getElementById("demo").innerHTML = obj;
</script>

//運行結果：[object Object]


<p id="demo"></p>
<script>
var
 
 text = ‘{"employees":[‘ +
‘{"name":"菜鳥教程","site":"http://www.runoob.com" },‘ +
‘{"name":"Google","site":"http://www.Google.com" },‘ +
‘{"name":"Taobao","site":"http://www.taobao.com" }]}‘;
obj = JSON.parse(text);
document.getElementById("demo").innerHTML =
obj.employees[1].name;
</script>

//運行結果：Google

<p id="demo"></p>
<script>
var person = {firstName:"John", lastName:"Doe", age:50, eyeColor:"blue"};
document.getElementById("demo").innerHTML = person;
</script>

//運行結果：[object Object]



<p id="demo"></p>
<script>
var person = {firstName:"John", lastName:"Doe", age:50, eyeColor:"blue"};
document.getElementById("demo").innerHTML = person.firstName;
</script>

//運行結果：John

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