jquery processing JSON and Ajax return JSON instance

First, some basic knowledge of JSON.

The objects in JSON are identified by "{}", and a "{}" represents an object, such as {"Areaid": "123"}, and the object's value is the form of a key-value pair (key:value).

"[]", identifies an array, and splits the data within the array through "," such as ["Areaid": "123", "Areaid": "345"].

In many cases it's an array of objects, and that's it:

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[{"Areaid": "123"},{"Areaid": "345"}]

In fact, an array is also an object, and the format above can be written like this:

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{' area ': [{' Areaid ': ' 123 '},{' areaid ': ' 345 '}]}

This represents an area object, which has two child data, each of which is an object, and each child object is areaid.

The definition format for strings and characters in JSON is similar to the general Class C language definition, with double quotes defining strings and single quotes defining characters.

The key in JSON is enclosed in double quotes, such as "area" and "Areaid", which are enclosed in double quotes, and you can use escape character escape double quotes when constructing JSON strings in some languages.

Two, javascript operation JSON characters

1, first to distinguish between JSON strings and JSON objects

JSON string:

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Var Strjson = ' {' area ': [{' Areaid ': ' 123 '},{' areaid ': ' 345 '}]} '

It can also be written in this way:

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Var Strjson = ' {' area ': [{' Areaid ': ' 123 '},{' areaid ': ' 345 '}]} ',

This represents a JSON string, because single and double quotes in JS can represent a string, so the first one to use double quotes and the second to use single quotes represents a JSON string.

Here's a look at the JSON object

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Var JSON = {"Area": [{"Areaid": "123"},{"Areaid": "345"}]},

See, the JSON object has no single or double quotes on the outside, which means a JSON object.

Script broken in server:

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<?php $data [' id '] = 1; $dat [' name '] = ' Mary '; $da [' Red ']= array_merge ($data, $dat); $data 1[' id '] = 2; $dat 1[' name '] = "swallow"; $da [' Blue ']= array_merge ($data 1, $dat 1); Print_r ($DA);///printed out is a two-dimensional array (as follows) /* Array ( [Red] => Array ( [ID] => 1 [Name] => Mary ) [Blue] => Array ( [ID] => 2 [Name] => Swallow ) ) */ echo Json_encode ($DA);//output is a string converted to JSON format, which can be used directly in JS (as follows) /* {"Red": {"id": 1, "name": "Mary"}, "Blue": {"id": 2, "name": "U71d5u5b50"}} */ ?>

jquery script:

Return to the processing after JS:
The first to use Varl conversion: When the string is the time to use eval into the jquery object (below)

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var arr = ' {' red ': {' id ': 1, ' name ': ' Mary '}, ' Blue ': {' id ': 2, ' name ': ' U71d5u5b50 '} ';//u71d5u5b50 this is automatically converted in PHP var dataobj = eval ("(" +arr+) ")//Here's the reason to add braces and double quotes. I don't know, just as JSON syntax, you can only memorize $.each (Dataobj,function (Idx,item) { Output Alert (item.id+ "haha" +item.name); })

The second: No need to transform:

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var arr = {"Red": {"id": 1, "name": "Mary"}, "Blue": {"id": 2, "name": "U71d5u5b50"}; $.each (Arr,function (Idx,item) { Output Alert (item.id+ "haha" +item.name); })

There are two ways of looping:
Method One:

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$.each (Arr,function (Idx,item) { Output Alert (item.id+ "haha" +item.name); })

Method Two:

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for (var key in arr) { alert (key); alert (arr[key].status); }

We can try the effect.

How Ajax is processed when it returns JSON

1, using the normal ASPX page to handle
I think this is the easiest way to deal with it, look at the code below

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$.ajax ({ Type: "Post", URL: "Default.aspx", DataType: "JSON", Success:function (data) { $ ("Input#showtime"). Val (Data[0].demodata); }, Error:function (XMLHttpRequest, Textstatus, Errorthrown) { alert (Errorthrown); } });

This is the code that passes the data in the background

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response.clear ();                          Response.Write ("[{" Demodata ":" This is the JSON Data "}]");                          Response.Flush ();                          Response.End ();

         this way of handling data that is passed directly into JSON data, In other words, the front desk JS code may directly parse the data into JSON object data, rather than string data, such as Data[0].demodata, where this JSON object data is used directly