JavaScript之Json的使用

时间:2023-03-09 18:10:20
JavaScript之Json的使用
  • Json字符串转JavaScript对象
 <html>
<body>
<h3>通过 JSON 字符串来创建对象</h3>
<p>
First Name: <span id="fname"></span><br />
Last Name: <span id="lname"></span><br />
</p>
<script type="text/javascript">
var txt = '{"employees":[' +
'{"firstName":"Bill","lastName":"Gates" },' +
'{"firstName":"George","lastName":"Bush" },' +
'{"firstName":"Thomas","lastName":"Carter" }]}'; obj = JSON.parse(txt); document.getElementById("fname").innerHTML=obj.employees[1].firstName
document.getElementById("lname").innerHTML=obj.employees[1].lastName
</script>
</body>
</html>

注意:

eval() 函数使用的是 JavaScript 编译器,可解析 JSON 文本,然后生成 JavaScript 对象。必须把文本包围在括号中,这样才能避免语法错误:

var obj = eval ("(" + txt + ")");
  • Json字符串转JavaScript对象2
 <html>
<body>
<h3>通过 JSON 字符串来创建对象</h3>
<p>
First Name: <span id="fname"></span><br />
Last Name: <span id="lname"></span><br />
</p>
<script type="text/javascript">
var txt = '{"employees":[' +
'{"firstName":"Bill","lastName":"Gates" },' +
'{"firstName":"George","lastName":"Bush" },' +
'{"firstName":"Thomas","lastName":"Carter" }]}'; var obj = eval ("(" + txt + ")"); document.getElementById("fname").innerHTML=obj.employees[1].firstName
document.getElementById("lname").innerHTML=obj.employees[1].lastName
</script>
</body>
</html>
  • JavaScript对象转JSON字符串
 </div>
<h3>JavaScript对象转换为Json字符串</h3>
<p>
all: <span id="all3"></span><br/>
</p>
<script type="text/javascript">
var txt = '{"employees":[' +
'{"firstName":"Bill","lastName":"Gates" },' +
'{"firstName":"George2","lastName":"Bush2" },' +
'{"firstName":"Thomas","lastName":"Carter" }]}'; var obj3 = eval("(" + txt + ")");
document.getElementById("all3").innerHTML = JSON.stringify(obj3);
</script>
<div>

来自:http://www.w3school.com.cn/json/json_eval.asp