Home Backend Development PHP Tutorial 单引号与双引号的区别解决方案

单引号与双引号的区别解决方案

Jun 13, 2016 pm 01:37 PM
explode post quot source

单引号与双引号的区别
textarea里有两行数据,name=source
aaaaaaaaaaa
bbbbbbbbbbb

我用explode("\r\n",$_POST['source'])结果有两个元素
用explode('\r\n',$_POST['source'])只有一个元素

------解决方案--------------------
至于你这个地方,可以很负责人的告诉你,是用单引号的。

比如$src = explode( ',', $src );
------解决方案--------------------
$str="hello";
echo '$str'; //解析不了 结果为:$str
echo "$str"; //解析了 结果为 hello

这就是单引号和双引号的区别 
 呵呵 查查资料吧 很久没有与php打交道了
------解决方案--------------------
php如果遇到双引号,会解析双引号里面的变量,如"$i"会被执行,显示i变量的值

但是如果你把'$i'变量放在单引号里,那Php就会直接输出$i也页面上显示,而不会显示变量i的实际值
------解决方案--------------------
双引号会对其中的变量展开,如$varname=hello, "123{$varname}123"最终为"123hello123";双引号会对其中的转义字符进行转义,如"\n\r"就是回车换行。
单引号不对变量展开;不对冒似转义字符进行转义,除了单引号本身,'\n\r'就是这4个字符,没什么其他意思。
------解决方案--------------------

探讨

php如果遇到双引号,会解析双引号里面的变量,如"$i"会被执行,显示i变量的值

但是如果你把'$i'变量放在单引号里,那Php就会直接输出$i也页面上显示,而不会显示变量i的实际值

------解决方案--------------------
探讨
textarea里有两行数据,name=source
aaaaaaaaaaa
bbbbbbbbbbb

我用explode("\r\n",$_POST['source'])结果有两个元素
用explode('\r\n',$_POST['source'])只有一个元素

------解决方案--------------------
在单引号串中甚至反斜杠也失去了他的扩展含义(除了插入反斜杠\\和插入单
引号\')。所以,当你想在字串中进行变量代换和包含\n(换行符)等转义序列时,你应该使用双引
号。
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Roblox: Bubble Gum Simulator Infinity - How To Get And Use Royal Keys
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Nordhold: Fusion System, Explained
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Mandragora: Whispers Of The Witch Tree - How To Unlock The Grappling Hook
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Java Tutorial
1666
14
PHP Tutorial
1272
29
C# Tutorial
1252
24
Analysis of how to use Source Insight in Ubuntu system Analysis of how to use Source Insight in Ubuntu system Jan 08, 2024 pm 11:49 PM

I believe that many friends are accustomed to using SourceInsight to read and analyze source code under Windows. There are indeed more efficient tools under LINUX, but it is troublesome and cumbersome to configure them. I believe many people definitely hope to be able to use them under Linux. SourceInsight can be used. The following editor will give you a detailed explanation of the use of SourceInsight in Ubuntu! Let’s go and see it together! This is my system information: Linuxgavin-laptop2.6.32-40-generic#87-UbuntuSMPTueMar600:56:56UTC2012x86_64GNU/Li

How to use python requests post How to use python requests post Apr 29, 2023 pm 04:52 PM

Python simulates the browser sending post requests importrequests format request.postrequest.post(url,data,json,kwargs)#post request format request.get(url,params,kwargs)#Compared with get request, sending post request parameters are divided into forms ( x-www-form-urlencoded) json (application/json) data parameter supports dictionary format and string format. The dictionary format uses the json.dumps() method to convert the data into a legal json format string. This method requires

What button is source? What button is source? Oct 10, 2023 pm 03:26 PM

Source is the button to switch the input signal source or select a different input source. Typically found on televisions, projectors, sound systems, computer monitors, and other equipment. On the TV, the source button allows users to switch between different input sources to play different content on the TV. On a projector, the source button has a similar function and can connect different devices to the projector. On the audio system, the source button is used to switch between different audio input sources. On computer monitors, the source button functions similarly to TVs and projectors, etc.

How does java initiate an http request and call the post and get interfaces? How does java initiate an http request and call the post and get interfaces? May 16, 2023 pm 07:53 PM

1. Java calls post interface 1. Use URLConnection or HttpURLConnection that comes with java. There is no need to download other jar packages. Call URLConnection. If the interface response code is modified by the server, the return message cannot be received. It can only be received when the response code is correct. to return publicstaticStringsendPost(Stringurl,Stringparam){OutputStreamWriterout=null;BufferedReaderin=null;StringBuilderresult=newSt

How to use PHP explode function and solve errors How to use PHP explode function and solve errors Mar 10, 2024 am 09:18 AM

The explode function in PHP is a function used to split a string into an array. It is very common and flexible. In the process of using the explode function, we often encounter some errors and problems. This article will introduce the basic usage of the explode function and provide some methods to solve the error reports. 1. Basic usage of the explode function In PHP, the basic syntax of the explode function is as follows: explode(string$separator,string$stri

A brief analysis of the POST method in PHP with parameters to jump to the page A brief analysis of the POST method in PHP with parameters to jump to the page Mar 23, 2023 am 09:15 AM

For PHP developers, using POST to jump to pages with parameters is a basic skill. POST is a method of sending data in HTTP. It can submit data to the server through HTTP requests. The jump page processes and jumps the page on the server side. In actual development, we often need to use POST with parameters to jump to pages to achieve certain functional purposes.

How to solve the problem that NGINX reverse proxy returns 405 for POST request of HTML page How to solve the problem that NGINX reverse proxy returns 405 for POST request of HTML page May 22, 2023 pm 07:49 PM

实现如下:server{listen80;listen443ssl;server_namenirvana.test-a.gogen;ssl_certificate/etc/nginx/ssl/nirvana.test-a.gogen.crt;ssl_certificate_key/etc/nginx/ssl/nirvana.test-a.gogen.key;proxy_connect_timeout600;proxy_read_timeout600;proxy_send_timeout600;c

How to implement PHP to jump to the page and carry POST data How to implement PHP to jump to the page and carry POST data Mar 22, 2024 am 10:42 AM

PHP is a programming language widely used in website development, and page jumps and carrying POST data are common requirements in website development. This article will introduce how to implement PHP page jump and carry POST data, including specific code examples. In PHP, page jumps are generally implemented through the header function. If you need to carry POST data during the jump process, you can do it through the following steps: First, create a page containing a form, where the user fills in the information and clicks the submit button. Acti in the form

See all articles