CSS counter-increment用法及代码示例

CSS counter-increment属性用于递增/递减计数器的值。 CSS计数器是一个变量，用于跟踪使用变量的次数。

用法:

counter-increment:none | identifier | initial | inherit;

属性值：

none:这是默认值，因此不会增加计数器。

用法:

counter-increment:none;

例：

<!DOCTYPE html> 
<html> 
  
<head> 
    <title>CSS counter-increment Property</title> 
    <style> 
      
        h1 { 
            color:green; 
        } 
          
        body { 
        } 
          
        <!-- The h2::before selector inserts something 
        before the content of each selected element -->
        h2::before { 
          
            counter-increment:none; 
        } 
    </style> 
</head> 
  
<body> 
  
    <h1>Welcome to GeeksforGeeks</h1> 
    <h1>Courses:</h1> 
    <h2>Fork Python</h2> 
    <h2>Fork Java</h2> 
    <h2>Fork CPP</h2> 
    <h2>Sudo Gate</h2> 
  
</body> 
  
</html>

输出：

identifier:标识符值用于定义要递增的计数器。该值也采用一个数字，该数字定义将进行多少增量。此增量值的默认值为1(如果尚未重置选择器，则默认值为0)。该值也取负值。

用法:

counter-increment:identifier;

例：

<!DOCTYPE html> 
<html> 
  
<head> 
    <title>CSS counter-increment Property</title> 
    <style> 
        
        h1 { 
            color:green; 
        } 
          
        body { 
            
            <!-- Set "geek-counter" identifier to 0 --> 
              counter-reset:geek-counter; 
        } 
          
        <!-- The h2::before selector inserts something 
          before the content of each selected element --> 
          h2::before { 
            
            <!-- Increment "geek-counter" by 1 --> 
            counter-increment:geek-counter; 
            content:"Course " counter(geek-counter) ":"; 
        } 
    </style> 
</head> 
  
<body> 
  
    <h1>Welcome to GeeksforGeeks</h1> 
    <h1>Courses:</h1> 
    <h2>Fork Python</h2> 
    <h2>Fork Java</h2> 
    <h2>Fork CPP</h2> 
    <h2>Sudo Gate</h2> 
  
</body> 
  
</html>

输出：

initial:此值将属性设置为其默认值。

用法:

counter-increment:initial;

例：

<!DOCTYPE html> 
<html> 
  
<head> 
    <style> 
    body { 
            /* Set "my-geek-counter" to 1*/ 
            counter-reset:my-geek-counter 1; 
        } 
          
        h2::before { 
            /* Sets the initial value  
              which is 1 here for the counter */ 
            counter-increment:initial; 
            content:"Section " counter(my-geek-counter) ". "; 
        } 
    } 
    </style> 
</head> 
  
<body> 
  
    <h1>Welcome to GeeksforGeeks</h1> 
    <h1>Courses:</h1> 
    <h2>Fork Python</h2> 
    <h2>Fork Java</h2> 
    <h2>Fork CPP</h2> 
    <h2>Sudo Gate</h2> 
</body> 
  
</html>

输出：

inherit:此值从其父元素继承此属性。

用法:

counter-increment:inherit;

例：

<!DOCTYPE html> 
<html> 
  
<head> 
    <style> 
    body { 
            /* Set "my-geek-counter" to 1*/ 
            counter-reset:my-geek-counter 1; 
        } 
          
        h2::before { 
            /* Sets the initial value  
            which is 1 here for the counter */ 
            counter-increment:inherit; 
            content:"Section " counter(my-geek-counter) ". "; 
        } 
    } 
    </style> 
</head> 
  
<body> 
  
    <h1>Welcome to GeeksforGeeks</h1> 
    <h1>Courses:</h1> 
    <h2>Fork Python</h2> 
    <h2>Fork Java</h2> 
    <h2>Fork CPP</h2> 
    <h2>Sudo Gate</h2> 
</body> 
  
</html>

输出：

支持的浏览器以下列出了counter-increment属性支持的浏览器：

谷歌浏览器2.0
Internet浏览器8.0
Firefox 1.0
Opera 9.2
苹果Safari 3.0

相关用法

注：本文由纯净天空筛选整理自Abhishek7大神的英文原创作品 CSS | counter-increment Property。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。