Bootstrap 4 - Immagini

Descrizione

Bootstrap 4 fornisce il supporto per le immagini utilizzando il tag <img>. Fornisce tre classi che possono essere utilizzate per applicare alcuni stili semplici alle immagini:

  • .img-round - Puoi rendere gli angoli arrotondati di un'immagine usando .rounded class.

  • .img-circle - Puoi rendere l'immagine come cerchio usando la classe .rounded-circle .

  • .img-thumbnail - Puoi rendere l'immagine come miniatura (bordo arrotondato di 1 pixel) usando la classe .img-thumbnail .

L'esempio seguente mostra l'utilizzo delle classi precedenti per dare uno stile a un'immagine:

Esempio

<html lang = "en">
   <head>
      <!-- Meta tags -->
      <meta charset = "utf-8">
      <meta name = "viewport" content = "width = device-width, initial-scale = 1, shrink-to-fit = no">
      
      <!-- Bootstrap CSS -->
      <link rel = "stylesheet" 
         href = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" 
         integrity = "sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" 
         crossorigin = "anonymous">
      
      <title>Bootstrap 4 Example</title>
   </head>
   
   <body>
      <div class = "container">
         <h2>Rounded Corners Image</h2>
         <img src = "https://www.tutorialspoint.com/bootstrap/images/64.jpg" 
            class = "rounded" alt = "Rounded Image" width = "200" height = "200"> 
         
         <p></p>
         <h2>Circle Image</h2>
         <img src = "https://www.tutorialspoint.com/bootstrap/images/64.jpg" 
            class = "rounded-circle" alt = "Rounded Image" width = "200" height = "200">
         
         <p></p>
         <h2>Thumbnail Image</h2>
         <img src = "https://www.tutorialspoint.com/bootstrap/images/64.jpg"
            class = "img-thumbnail" alt = "Rounded Image" width = "200" height = "200">
      </div>
      
      <!-- jQuery first, then Popper.js, then Bootstrap JS -->
      <script src = "https://code.jquery.com/jquery-3.3.1.slim.min.js" 
         integrity = "sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" 
         crossorigin = "anonymous">
      </script>
      
      <script src = "https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js" 
         integrity = "sha384-ZMP7rVo3mIykV+2+9J3UJ46jBk0WLaUAdn689aCwoqbBJiSnjAK/l8WvCWPIPm49" 
         crossorigin = "anonymous">
      </script>
      
      <script src = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js" 
         integrity = "sha384-ChfqqxuZUCnJSK3+MXmPNIyE6ZbWh2IMqE241rYiqJxyMiZ6OW/JmZQ5stwEULTy" 
         crossorigin = "anonymous">
      </script>
      
   </body>
</html>

Produrrà il seguente risultato:

Produzione

Allineamento delle immagini

L'immagine può essere spostata a sinistra utilizzando la classe .float-left ea destra utilizzando la classe .float-right .

L'esempio seguente mostra l'allineamento delle immagini:

Esempio

<html lang = "en">
   <head>
      <!-- Meta tags -->
      <meta charset = "utf-8">
      <meta name = "viewport" content = "width = device-width, initial-scale = 1, shrink-to-fit = no">
      
      <!-- Bootstrap CSS -->
      <link rel = "stylesheet" 
         href = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" 
         integrity = "sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" 
         crossorigin = "anonymous">
      
      <title>Bootstrap 4 Example</title>
   </head>
   
   <body>
      <div class = "container">
         <h2>Aligning Images</h2>
         <br>
         <img src = "https://www.tutorialspoint.com/bootstrap/images/64.jpg" 
            class = "float-left" alt = "Left Image" width = "200" height = "200"> 
         
         <img src = "https://www.tutorialspoint.com/bootstrap/images/64.jpg" 
            class = "float-right" alt = "Right Image" width = "200" height = "200">
            
         <p></p>
      </div>
      
      <!-- jQuery first, then Popper.js, then Bootstrap JS -->
      <script src = "https://code.jquery.com/jquery-3.3.1.slim.min.js" 
         integrity = "sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" 
         crossorigin = "anonymous">
      </script>
      
      <script src = "https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js" 
         integrity = "sha384-ZMP7rVo3mIykV+2+9J3UJ46jBk0WLaUAdn689aCwoqbBJiSnjAK/l8WvCWPIPm49" 
         crossorigin = "anonymous">
      </script>
      
      <script src = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js" 
         integrity = "sha384-ChfqqxuZUCnJSK3+MXmPNIyE6ZbWh2IMqE241rYiqJxyMiZ6OW/JmZQ5stwEULTy" 
         crossorigin = "anonymous">
      </script>
      
   </body>
</html>

Produrrà il seguente risultato:

Produzione

Centrare le immagini

È possibile posizionare un'immagine al centro utilizzando le classi .mx-auto (margin: auto) e .d-block (display: block).

L'esempio seguente mostra il posizionamento di un'immagine al centro:

Esempio

<html lang = "en">
   <head>
      <!-- Meta tags -->
      <meta charset = "utf-8">
      <meta name = "viewport" content = "width = device-width, initial-scale = 1, shrink-to-fit = no">
      
      <!-- Bootstrap CSS -->
      <link rel = "stylesheet" 
         href = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" 
         integrity = "sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" 
         crossorigin = "anonymous">
      
      <title>Bootstrap 4 Example</title>
   </head>
   
   <body>
      <div class = "container">
         <h2>Centered Image</h2>
         <img src = "https://www.tutorialspoint.com/bootstrap/images/64.jpg" 
            class = "mx-auto d-block" alt = "Center Image" width = "200" height = "200">
      </div>
      
      <!-- jQuery first, then Popper.js, then Bootstrap JS -->
      <script src = "https://code.jquery.com/jquery-3.3.1.slim.min.js" 
         integrity = "sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" 
         crossorigin = "anonymous">
      </script>
      
      <script src = "https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js" 
         integrity = "sha384-ZMP7rVo3mIykV+2+9J3UJ46jBk0WLaUAdn689aCwoqbBJiSnjAK/l8WvCWPIPm49" 
         crossorigin = "anonymous">
      </script>
      
      <script src = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js" 
         integrity = "sha384-ChfqqxuZUCnJSK3+MXmPNIyE6ZbWh2IMqE241rYiqJxyMiZ6OW/JmZQ5stwEULTy" 
         crossorigin = "anonymous">
      </script>
      
   </body>
</html>

Produrrà il seguente risultato:

Produzione

Immagini reattive

Puoi rendere le immagini reattive (regolate automaticamente per adattarsi alle dimensioni dello schermo tra i dispositivi) utilizzando la classe .img-fluid (fornisce la larghezza massima: 100%; e l' altezza: auto; all'immagine).

L'esempio seguente mostra la visualizzazione di responsive nel documento:

Esempio

<html lang = "en">
   <head>
      <!-- Meta tags -->
      <meta charset = "utf-8">
      <meta name = "viewport" content = "width = device-width, initial-scale = 1, shrink-to-fit = no">
      
      <!-- Bootstrap CSS -->
      <link rel = "stylesheet" 
         href = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" 
         integrity = "sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" 
         crossorigin = "anonymous">
      
      <title>Bootstrap 4 Example</title>
   </head>
   <body>
      <div class="container">
         <h2>Responsive Image</h2>
         <img src = "https://www.tutorialspoint.com/bootstrap/images/64.jpg" 
            class = "img-fluid" alt = "Responsive Image" width = "200" height = "200">
      </div>
      
      <!-- jQuery first, then Popper.js, then Bootstrap JS -->
      <script src = "https://code.jquery.com/jquery-3.3.1.slim.min.js" 
         integrity = "sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" 
         crossorigin = "anonymous">
      </script>
      
      <script src = "https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js" 
         integrity = "sha384-ZMP7rVo3mIykV+2+9J3UJ46jBk0WLaUAdn689aCwoqbBJiSnjAK/l8WvCWPIPm49" 
         crossorigin = "anonymous">
      </script>
      
      <script src = "https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js" 
         integrity = "sha384-ChfqqxuZUCnJSK3+MXmPNIyE6ZbWh2IMqE241rYiqJxyMiZ6OW/JmZQ5stwEULTy" 
         crossorigin = "anonymous">
      </script>
      
   </body>
</html>

Produrrà il seguente risultato:

Produzione