d3.js band.copy()用法及代码示例

band.copy()函数用于构造并返回具有相同域和范围的当前音阶的副本。对任何比例进行的任何更改都是相互独立的，即原始比例的更改不会影响复印比例，反之亦然。

用法:

band.copy();

参数：此函数不接受任何参数。

返回值：此函数返回当前刻度的副本。返回类型是一个函数。

下面给出的是上面给出的函数的一些例子。

范例1：

<!DOCTYPE html>  
<html lang = "en">  
<head>  
    <meta charset = "UTF-8" />  
    <meta name = "viewport"
        path1tent = "width=device-width,  
        initial-scale = 1.0"/>  
    <script src = 
    "https://d3js.org/d3.v4.min.js"> 
    </script> 
      
</head>  
<body>  
    <script>  
    // Creating the band scale  
    //with specified domain and range. 
        var band = d3.scaleBand() 
                    .domain([10, 20, 30, 40, 50]) 
                    .range([10, 100]); 
    // Discrete values are automatically created  
    // By the band function 
    // Band of the range is [10, 100] 
        console.log("band(10):", band(10)); 
        console.log("band(50):", band(50)); 
  
        var bandCopy = band.copy(); 
        console.log("bandCopy(10):", bandCopy(10)); 
        console.log("bandCopy(50):", bandCopy(50)); 
    </script>  
</body>  
</html>

输出：

范例2：

<!DOCTYPE html>  
<html lang = "en">  
<head>  
    <meta charset = "UTF-8" />  
    <meta name = "viewport"
        path1tent = "width=device-width,  
        initial-scale = 1.0"/>  
    <title>GeekforGeeks</title>  
    <script src = 
    "https://d3js.org/d3.v4.min.js"> 
    </script> 
      
</head>  
<body>  
    <script>  
    // Creating the band scale 
  // with specified domain and range. 
        var band = d3.scaleBand() 
                .domain([10, 20, 30, 40, 50]) 
                .range([1, 10]); 
// Discrete values are automatically created  
    // By the band function 
    // Band of the range is [1, 10] 
        console.log( 
"Before any type of change in original scale:"); 
        console.log("band(10):", band(10)); 
        console.log("band(50):", band(50)); 
        // Making copy of the original scale 
        var bandCopy = band.copy(); 
        console.log( 
"When the range of the original "+ 
"scale is changed to rangeRound:"); 
        // Making changes to the original scale 
        band.rangeRound([1, 10]); 
        console.log("band(10):", band(10)); 
        console.log("band(50):", band(50)); 
        console.log("Output of the copy scale:"); 
        console.log("bandCopy(10):", bandCopy(10)); 
        console.log("bandCopy(50):", bandCopy(50)); 
    </script>  
</body>  
</html>

输出：

相关用法

注：本文由纯净天空筛选整理自tarun007大神的英文原创作品 D3.js band.copy() Function。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。