Question

例如我有一个像

这样的文字

<p>
Quis vel accusantium libero. Suscipit officiis culpa
<img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7">
libero quia ad.
</p>

我想检查字符串是否有data:image然后只截断这部分，因此max char为50，所以结果变为

<p>
Quis vel accusantium libero. Suscipit officiis culpa
<img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH...">
libero quia ad.
</p>

我不确定如何使用preg_replace和"data:image.+?"模式

来实现这一目标

Answer 1

问题：PHP字符串解析

感谢您通过评论澄清您的问题。您似乎想要的是一个通用 HTML解析器，它可以对HTML标记进行特殊情况修改。
一般来说，is not advisable to use regex to parse HTML。
如果您想要一个通用工具（而不是一种快速而肮脏的方法），那么SO已经有一个关于Modifying html attributes with PHP可能更接近您想要的问题。
如果你想要的是一个快速而又脏的方法，它将从img标签上的src属性中删除长的base64编码数据，那么你可以标记原始HTML字符串，并且然后执行正则表达式替换，但如果您决定要进行其他修改，那么这种方法将会很痛苦。当你刚开始使用真正的HTML解析器时，你可能最终会重新发明轮子。
尽管如此，下面的方法就是这样做，将字符串标记化，进行替换，然后返回整个修改过的字符串。

使用preg_replace（快速和脏）

的解决方案

<?php

$demostring = '
<p>
Quis vel accusantium libero. Suscipit officiis culpa
<img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7">
libero quia ad.
</p>
';

function ctf0_truncate($vinput){
  return( preg_replace('/(data:image.{50})(.*)/', '$1', $vinput) );
}

function ctf0_parse($text, $chars = 50) {
  if (strpos($text, 'data:image') !== FALSE){
    $tokens = explode('"',$text);
    $tokens = array_map("ctf0_truncate",$tokens);
    $vout   = implode('"',$tokens);
  } elseif( True ) {
    $vout = $text;
  }
  return $vout;
}

$myresult = ctf0_parse($demostring);
print($myresult);

输出结果

<p>
Quis vel accusantium libero. Suscipit officiis culpa
<img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALA">
libero quia ad.
</p>

备注

上述解决方案省略了问题的请求元素。具体来说，如何添加＆＃39; ...＆＃39; 省略号。对于该部分，请参阅有关SO的其他答案，例如here和here。

Answer 2

您可以通过<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.auth0.samples</groupId> <artifactId>spring-boot-faces</artifactId> <version>1.0-SNAPSHOT</version>  <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.2.RELEASE</version> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> <spring.security>4.1.3.RELEASE</spring.security> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> </properties>  <dependencies>  <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-validation</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>net.sf.dozer</groupId> <artifactId>dozer</artifactId> <version>5.4.0</version> </dependency>  <dependency> <groupId>org.apache.myfaces.core</groupId> <artifactId>myfaces-impl</artifactId> <version>2.2.12</version> </dependency> <dependency> <groupId>org.apache.myfaces.core</groupId> <artifactId>myfaces-api</artifactId> <version>2.2.12</version> </dependency> <dependency> <groupId>org.apache.tomcat.embed</groupId> <artifactId>tomcat-embed-jasper</artifactId> </dependency>  <dependency> <groupId>org.primefaces</groupId> <artifactId>primefaces</artifactId> <version>6.1</version> </dependency>   <dependency> <groupId>org.postgresql</groupId> <artifactId>postgresql</artifactId> <version>9.4-1200-jdbc41</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-c3p0</artifactId> <version>4.1.7.Final</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-entitymanager</artifactId> <version>4.3.10.Final</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-core</artifactId> <version>4.3.10.Final</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-aop</artifactId> </dependency> <dependency> <groupId>org.liquibase</groupId> <artifactId>liquibase-core</artifactId> </dependency> <dependency> <groupId>org.springframework.security</groupId> <artifactId>spring-security-web</artifactId> <version>${spring.security}</version> </dependency> <dependency> <groupId>org.springframework.security</groupId> <artifactId>spring-security-config</artifactId> <version>${spring.security}</version> </dependency> <dependency> <groupId>org.springframework.security</groupId> <artifactId>spring-security-core</artifactId> <version>${spring.security}</version> </dependency> <dependency> <groupId>org.springframework.security</groupId> <artifactId>spring-security-openid</artifactId> <version>${spring.security}</version> </dependency> <dependency> <groupId>org.springframework.security</groupId> <artifactId>spring-security-ldap</artifactId> <version>${spring.security}</version> </dependency>    <dependency> <groupId>jstl</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency>   <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>4.0-alpha4</version> </dependency> <dependency> <groupId>org.eclipse.persistence</groupId> <artifactId>eclipselink</artifactId> <version>2.5.2</version> </dependency> <dependency> <groupId>org.eclipse.persistence</groupId> <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId> <version>2.5.2</version> <scope>provided</scope> </dependency> <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3</version> </dependency> <dependency> <groupId>commons-io</groupId> <artifactId>commons-io</artifactId> <version>2.2</version> </dependency>  <dependency> <groupId>com.lowagie</groupId> <artifactId>itext</artifactId> <version>2.1.7</version> </dependency>  <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi</artifactId> <version>3.7</version> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi-ooxml</artifactId> <version>3.10.1</version> </dependency>  <dependency> <groupId>javax.inject</groupId> <artifactId>javax.inject</artifactId> <version>1</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.16.18</version> <scope>provided</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-security</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-security</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-security</artifactId> </dependency> </dependencies>  <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>（_ all），preg_match等方式以不同方式执行此操作。

但preg_split的效果如下：run to see

preg_replace

如何在php

2 个答案:

问题：PHP字符串解析

使用preg_replace（快速和脏）

输出结果

备注