Seven data types that novices must know when getting started with PHP

If you want to get started with PHP, you must first learn to set up an environment, and secondly learn basic syntax. The basics of PHP include data types, operators, variables and constants, etc.

In this article, we mainly understand what data types are. Data type refers to a general term for the same type of data, generally described as XX data type.

For example, integers and decimals are both numbers, we will collectively refer to them as numeric data types. In PHP, data types are divided into 7 categories, as shown in the figure:

Examples of PHP data types are as follows:

<?php 
/*字符串（String）：
指单引号或双引号包住的一串字符*/
echo "12rqwr#@%";
echo &#39;rq#@wr12%&#39;;
/*整型（Integer）：
指整数，不能有小数点，可正数或负数*/
echo 3124;
echo -3124;
/*浮点型（Float）：
指有小数点的整数或小数，以及指数*/
echo 0.35;
echo 3.0;
/*布尔型（Boolean）：
指是或非，用True和False表示*/
echo True;
echo False;
/*数组（Array）：
指一组数据的集合，数据包含字符串和整型，浮点型等*/
print_r(array(&#39;hello&#39;,124,&#39;world&#39;,0.15));
/*对象（Object）：
包含属性和方法的结构，详情查看对象篇*/
class ClassName extends AnotherClass
{
  function __construct(argument)
{
    # code...
  }
}
/*空值（null）：
表示没有值，数据为空*/
echo null;
?>

In the above example, Add two basic knowledge points: comments and printout. Comments are intended to be notes and have no impact on the program. They are just to facilitate developers to understand the program. The printout is intended to display the results.

There are 2 types of comments in PHP, examples are as follows:

//双斜线用于注释单行
/*这个符号用于注释多行*/

There are 3 types of printouts in PHP, examples are as follows:

<?php 
/*显示字符串类型，整数类型
浮点类型，空值*/
echo 123;
echo "string";
echo 0.35;
echo null;
// 显示数组类型
print_r();
// 显示数组类型，显示判断条件的是与非
// 比print_r()显示的更详细
var_dump();
?>

Another thing to note is, Every time you write a complete sentence of code, it must end with the English symbol;, otherwise an error will occur.

PHP Chinese website has a large number of free PHP video tutorials, everyone is welcome to learn!

This article is reproduced from: https://www.php.cn/course/list/29.html

The above is the detailed content of Seven data types that novices must know when getting started with PHP. For more information, please follow other related articles on the PHP Chinese website!