jquery的-extend函數

時間 2019-12-14

標籤 jquery extend 函數欄目 JQuery 简体版

原文原文鏈接

js的淺拷貝與深拷貝：javascript

淺拷貝：JS中引用類型使用等號「=」賦值，至關於把原來對象的地址拷貝一份給新的對象，這樣原來舊的對象與新的對象就指向同一個地址，改變其中一個對象就會影響另外那個對象，也就是所謂的淺拷貝。html

深拷貝：所謂」深拷貝」，就是可以實現真正意義上的數組和對象的拷貝。它的實現並不難，只要遞歸調用」淺拷貝」就好了。指向不一樣的地址。java

3.代碼示例：http://api.jquery.com/jQuery.extend/#jQuery-extend-target-object1-objectNjquery

<!doctype html>

<html lang="en">

<head>

<meta charset="utf-8">

<title>jQuery.extend demo</title>

<script src="https://code.jquery.com/jquery-1.10.2.js"></script>

</head>

<body>

<div id="log"></div>

<script>

var object1 = {

apple: 0,

banana: { weight: 52, price: 100 },

cherry: 97

};

var object2 = {

banana: { price: 200 },

durian: 100

};

// Merge object2 into object1

$.extend( object1, object2 );

// Assuming JSON.stringify - not available in IE<8

$( "#log" ).append( JSON.stringify( object1 ) );

</script>

</body>

 
  </html> 
 
    <!doctype html> 
   
    <html lang="en"> 
   
    <head> 
   
     <meta charset="utf-8"> 
   
     <title>jQuery.extend demo</title> 
   
     <script src="https://code.jquery.com/jquery-1.10.2.js"></script> 
   
    </head> 
   
    <body> 
   
    <div id="log"></div> 
   
    <script> 
   
    var object1 = { 
   
     apple: 0, 
   
     banana: { weight: 52, price: 100 }, 
   
     cherry: 97 
   
    }; 
   
    var object2 = { 
   
     banana: { price: 200 }, 
   
     durian: 100 
   
    }; 
   
    // Merge object2 into object1, recursively 
   
    $.extend( true, object1, object2 ); 
   
    // Assuming JSON.stringify - not available in IE<8 
   
    $( "#log" ).append( JSON.stringify( object1 ) ); 
   
    </script> 
   
    </body> 
   
    </html> 
   
      <!doctype html> 
     
      <html lang="en"> 
     
      <head> 
     
       <meta charset="utf-8"> 
     
       <title>jQuery.extend demo</title> 
     
       <script src="https://code.jquery.com/jquery-1.10.2.js"></script> 
     
      </head> 
     
      <body> 
     
      <div id="log"></div> 
     
      <script> 
     
      var defaults = { validate: false, limit: 5, name: "foo" }; 
     
      var options = { validate: true, name: "bar" }; 
     
      // Merge defaults and options, without modifying defaults 
     
      var settings = $.extend( {}, defaults, options ); 
     
      // Assuming JSON.stringify - not available in IE<8 
     
      $( "#log" ).append( "<div><b>defaults -- </b>" + JSON.stringify( defaults ) + "</div>" ); 
     
      $( "#log" ).append( "<div><b>options -- </b>" + JSON.stringify( options ) + "</div>" ); 
     
      $( "#log" ).append( "<div><b>settings -- </b>" + JSON.stringify( settings ) + "</div>" ); 
     
      </script> 
     
      </body> 
     
      </html>