On the _javascript techniques of JavaScript string and array

JavaScript string

A string is a collection of characters, including English letters, punctuation marks, special symbols, Chinese characters, and so on.

In JavaScript, strings can be represented by double quotes ("") or single quotes (' ").

Double quotes and single quotes must appear in pairs, which can contain single quotes, and can contain double quotes inside the single quotation mark.

For example:

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var mystr1= "My name is ' Xiaohua '!" ";
var mystr2= ' "Is my dream!", Tom said. ' ;

The length of the string is obtained by the lengths, for example:

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Mystr1.length;
Mystr2.length;

JavaScript array

Arrays are used to store a series of values in a separate variable.

In JavaScript, you can define an array in several ways.

Use keyword new to create an array object

For example, create an array named MyArray and assign the value:

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var myarray=new Array ();
Myarray[0] = "zhangming";
MYARRAY[1] = "Zhaowei";
MYARRAY[2] = "Wanghua";

You can also assign values while creating an object:

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var myarray=new Array ("zhangming", "Zhaowei", "Wanghua");

Create an array directly using []

For example, create an array named MyArray and assign the value:

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var myarray=[];
Myarray[0] = "zhangming";
MYARRAY[1] = "Zhaowei";
MYARRAY[2] = "Wanghua";

Of course, you can also assign values at the same time you create an array:

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var myarray=["zhangming", "Zhaowei", "Wanghua"];

Create a group of key/value pairs

For example, create an array named MyArray and assign the value:

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var myarray=new Array (); You can also use Var myarray=[];
myarray["zhangming"] = "22";
myarray["Zhaowei"] = "21";
myarray["Wanghua"] = "30";

Modifying an array

Arrays can be modified after they are created and assigned, for example:

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Myarray[0] = "zhangming_1";
MYARRAY[1] = "zhaowei_1";
myarray["zhangming"] = "42";
myarray["Zhaowei"] = "61";

Array length

In JavaScript, you get the length of an array by length, for example:

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Myarray.length

The above mentioned is the entire content of this article, I hope you can enjoy.