eval解析json字符串可用的三种方式都可以实现。。。
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<script type="text/javascript">
//json以数组方式存在
var data = "[{"book1":"javabook1","book2":"javabook2"}]";
var json = eval("("+data+")");
document.write(json[0].book1);
document.write("<br/>");
document.write(json[0].book2);
</script>
<br/><br/>
<script type="text/javascript">
//json中只有一个对象，且内双引号用的转义字符
var data1 = "{"book1":"javabook1","book2":"javabook2"}";
var json1 = eval("("+data1+")");
document.write(json1.book1);
document.write("<br/>");
document.write(json1.book2);
</script>
<br/><br/>
<script type="text/javascript">
//json中只有一个对象，且双引号可以包单引号
var data2 = "{'book1':'javabook1','book2':'javabook2'}";
var json2 = eval("("+data2+")");
document.write(json2.book1);
document.write("<br/>");
document.write(json2.book2);
</script>
</body>
</html>