


In the previous article, we learned about the method of using the "natural" algorithm to know the similarities and differences of strings. If you need it, please read "How to use the "natural" algorithm to know the similarities and differences of strings". This time we introduce to you another method of using the "natural" algorithm to know the similarities and differences of strings. You can refer to it if you need it.
In the previous article, we introduced a "natural" algorithm that is case-insensitive. But, friends, do you have any doubts? When using it, if you need to ensure that the letters in a string are in the same case, how should you write it? Today I will tell you how a case-sensitive "natural" algorithm compares strings.
Let us look at a little chestnut.
<?php echo strnatcmp("2Hello WORLD!","10Hello WORLD!"); echo "<br>"; echo strnatcmp("2hello world!","2aello world!"); echo "<br>"; echo strnatcmp("2hello world!","9hello WORLD!"); echo "<br>"; echo strnatcmp("2hello world!","2HELLO WORLD!"); echo "<br>"; echo strnatcmp("2hello world!","2hello world!"); ?>
The result is
Let’s take a look at this result. The result of this function still uses “0
”, “ -1
", "1
" to represent the result of comparison between two functions. Let’s look at this example
When we have the same number except for the previous number, we find that the number is -1, which means that the first string is smaller than the second string; when our numbers are the same, but the following When the letters change, it is 1, which means that the first string is greater than the second string; and when the numbers are the same, the letters are the same, and the upper and lower case are different, it is found to be 1; only when the numbers, letters, And when the uppercase and lowercase letters are exactly the same, it is 0, that is, the two strings are equal.
Then let’s take a look at this function.
The strnatcmp() function uses a "natural" algorithm to compare two strings (case sensitive). In natural arithmetic, the number 2 is less than the number 10. In computer sorting, 10 is less than 2 because the first number in 10 is less than 2.
The syntax of this function is
strnatcmp(要比较的第一个字符串,要比较的第二个字符串)
These are the same as the functions we introduced in the previous article, but we still have to look at the return value of this function.
This function returns:
0 - if the two strings are equal
>0 - If string1 is greater than string2
That’s it. If you want to know anything else, you can click this. → →php video tutorial
The above is the detailed content of PHP uses one trick to compare the similarities and differences of strings using the 'natural' algorithm (case sensitive). For more information, please follow other related articles on the PHP Chinese website!

php把负数转为正整数的方法:1、使用abs()函数将负数转为正数,使用intval()函数对正数取整,转为正整数,语法“intval(abs($number))”;2、利用“~”位运算符将负数取反加一,语法“~$number + 1”。

实现方法:1、使用“sleep(延迟秒数)”语句,可延迟执行函数若干秒;2、使用“time_nanosleep(延迟秒数,延迟纳秒数)”语句,可延迟执行函数若干秒和纳秒;3、使用“time_sleep_until(time()+7)”语句。

php除以100保留两位小数的方法:1、利用“/”运算符进行除法运算,语法“数值 / 100”;2、使用“number_format(除法结果, 2)”或“sprintf("%.2f",除法结果)”语句进行四舍五入的处理值,并保留两位小数。

判断方法:1、使用“strtotime("年-月-日")”语句将给定的年月日转换为时间戳格式;2、用“date("z",时间戳)+1”语句计算指定时间戳是一年的第几天。date()返回的天数是从0开始计算的,因此真实天数需要在此基础上加1。

php字符串有下标。在PHP中,下标不仅可以应用于数组和对象,还可应用于字符串,利用字符串的下标和中括号“[]”可以访问指定索引位置的字符,并对该字符进行读写,语法“字符串名[下标值]”;字符串的下标值(索引值)只能是整数类型,起始值为0。

方法:1、用“str_replace(" ","其他字符",$str)”语句,可将nbsp符替换为其他字符;2、用“preg_replace("/(\s|\ \;||\xc2\xa0)/","其他字符",$str)”语句。

php判断有没有小数点的方法:1、使用“strpos(数字字符串,'.')”语法,如果返回小数点在字符串中第一次出现的位置,则有小数点;2、使用“strrpos(数字字符串,'.')”语句,如果返回小数点在字符串中最后一次出现的位置,则有。

在php中,可以使用substr()函数来读取字符串后几个字符,只需要将该函数的第二个参数设置为负值,第三个参数省略即可;语法为“substr(字符串,-n)”,表示读取从字符串结尾处向前数第n个字符开始,直到字符串结尾的全部字符。


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

SublimeText3 Linux new version
SublimeText3 Linux latest version

SublimeText3 Chinese version
Chinese version, very easy to use

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Mac version
God-level code editing software (SublimeText3)
