Json.stringify Syntax Examples Explained

It is not a short time to know JavaScript, but this usage is true, I have seen it for the first time, ashamed ah ashamed ah. Thus, on the Internet to write information, wrote some examples hope to give some help to the garden. role: This function is mainly for the purpose of serialization objects. Maybe some people are allergic to the word serialization, my understanding is very simple. This means converting the type of the object to a string type (or, more specifically, the JSON type). It's so simple. For example, you have a class, so you can convert it to the corresponding JSON type by this method. It's simple. Then look. Syntax: Json.stringify (value [, Replacer] [, Space]) value: is the required field. Is the object you have entered, such as array Ah, class AH and so on. Replacer: This is optional. It is divided into 2 ways, one is method, the second is an array. Situation one: We first say the data, through the experiment behind us, we can know that it is related to the first one. In general, our serialization results are represented by key-value pairs. For example: Name: "LAN", age:25 this form. So, if this is the case, if the value of the second exists in the first, then the value of the second is the key, the first value for value is represented, if it does not exist, sorry, ignore. "It's not a bit abstract, I think so, but you just wait and see the experiment is OK." Whirring "Situation Two: if it is a method, it is very simple, that is, the serialization of each object (remember that each one) into the method of processing." Space: Well understood, with what to do the delimiter. 1. If omitted, then the displayed value does not have a separator character. Direct output to 2. If it is a number, then it defines the indentation of several characters, of course, if it is greater than 10, the maximum value is 10. 3. If there are some escape characters, such as "\ T", which means carriage return, then it is a carriage return per line. 4. If it is just a string, OK, append the strings to the output value in each row. Of course, the maximum length is also 10 characters. begin to illustrate with examples; 1. In the case of only one parameter:

Copy CodeThe code is as follows: var student = new Object (); Student.name = "Lanny"; Student.age = "25"; student.location = "China"; var json = json.stringify (student); alert (student);

The results are as follows: Some people may doubt the role of Json.stringify, OK. Well, if we don't want this function. The code looks like this:

Copy CodeThe code is as follows: var student = new Object (); Student.name = "Lanny"; Student.age = "25"; student.location = "China";
var json = json.stringify (student); alert (student);

Congratulations on the results you've got:

Don't lie to you, go on. 2. The second parameter is present, and the second argument is a function.

Copy CodeThe code is as follows: var students = new Array (); Students[0] = "Lanny"; Students[1] = "dong"; STUDENTS[2] = "I love You"; var json = json.stringify (students,switchupper); function Switchupper (key, value) {return value.tostring (). toUpperCase ();} alert (JSON);
var json = json.stringify (students, function (Key,value) {
Return value.tostring (). toUpperCase ();
//});

The above method can also be replaced by the following, 2 are the same, but the wording of a little bit different. The results were as follows:

3. The second parameter exists, and the second parameter is not a function, but an array. 3.1 "Misunderstanding" if the first parameter is an array, the second argument is an array, only the value of the first parameter is displayed. Like what:

Copy CodeThe code is as follows: var students = new Array (); Students[0] = "Lanny"; Students[1] = "dong"; STUDENTS[2] = "I love You"; var stu = new Array (); Stu[0] = "1"; STU[1] = "2"; var json = json.stringify (STUDENTS,STU); alert (JSON);

The result of the sorry is that the second one is ignored, but the first one is serialized.
3.2 If the first is an object (the object here is like a new in C #), the second one is an array.
Then if the value of the second exists in the first, then the second value is the key, and the first value is represented as value.

Copy CodeThe code is as follows: var student = new Object (); STUDENT.QQ = "5485891512"; Student.name = "Lanny"; Student.age = 25;
var stu = new Array (); Stu[0] = "QQ"; STU[1] = "age"; STU[2] = "Hi";//This student object does not exist.
var json = json.stringify (STUDENT,STU); alert (JSON);

The results are as follows: because stu[2] = "HI"; this hi is not found in the first one, so it is not displayed.
4. A third parameter
4.1. If omitted, then the displayed value does not have a separator character. Direct output to
Like what:

Copy CodeThe code is as follows: var student = new Object (); STUDENT.QQ = "5485891512"; Student.name = "Lanny"; Student.age = 25;
var stu = new Array (); Stu[0] = "QQ"; STU[1] = "age"; STU[2] = "Hi";
var json = json.stringify (STUDENT,STU); alert (JSON);

The output is: 4.2. If it is a number, then it defines the indentation of several characters, of course, if it is greater than 10, the maximum value is 10.

Copy CodeThe code is as follows: var student = new Object (); STUDENT.QQ = "5485891512"; Student.name = "Lanny"; Student.age = 25;
var stu = new Array (); Stu[0] = "QQ"; STU[1] = "age"; STU[2] = "Hi";
var json = json.stringify (student,stu,100);//note here the alert (JSON);

So the resulting is: 10 characters are empty.
4.3. If there are some escape characters, such as "\ T", which means carriage return, then it is a carriage return per line.
is the same.
4.4. If it is just a string, OK, append the strings to the output value in each row. Of course, the maximum length is also 10 characters.
If it is var json = json.stringify (Student,stu, "Haikou");//

Json.stringify Syntax Examples Explained