When the JSON value returned by Eval, firebug prompts error: Invalid label)

Http://hi.baidu.com/mallor/blog/item/22a4dc1f9497a465f724e4e3.html

We often return a value in JSON format on the server side, which can be directly used as a complete object in the script. However, many new users usually encounter an error message: Invalid label, this problem is often distressing, because the correct JSON format is prompted with an error.

Assume that you return a JSON string from the server:

Javascript:

 
 

  
  
 
  
  
{
  
  
siteName : "CodeBit.cn",
  
  
siteUrl : "http://www.CodeBit.cn"
  
  
}
  
  
 
 
 

Run the following command in eval mode in the script:

Javascript:

 
 

  
  
 
  
  
var result = eval(o.responseText);
  
  
alert(result.siteName);
  
  
 
 
 

The following message is displayed:Error: Invalid label

In fact, our JSON format is not incorrect, but when Eval is used, you should enclose your JSON value in brackets:

Javascript:

 
 

  
  
 
  
  
var result = eval("(" + o.responseText + ")");
  
  
alert(result.siteName);
  
  
 
 
 

Haha, this is often the easiest to ignore, but once there is an error, it is also the most headache :)