d3.js node.each()用法及代碼示例

node.each()函數用於按廣度優先順序評估每個節點的函數。在這種情況下，每個節點正好被訪問一次。對於每個子節點重複調用此函數。

用法:

node.each(function);

參數：該函數接受如上所述和以下描述的單個參數：

function:這需要在BFS順序中的每個節點上調用一個函數。

返回值：此函數不返回任何內容。

範例1：

HTML

<!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>  
    // Constructing a tree 
    var tree={ 
            name:"rootNode", 
            children:[ 
                { 
                    name:"child1" 
                }, 
                { 
                    name:"child2", 
                    children:[ 
                        { 
                            name:"grandchild1", 
                            children:[ 
                                { 
                                    name:"grand_granchild1_1" 
                                }, 
                                { 
                                    name:"grand_granchild1_2" 
                                } 
                            ] 
                        }, 
                        { 
                            name:"grandchild2", 
                            children:[ 
                                { 
                                    name:"grand_granchild2_1" 
                                }, 
                                { 
                                    name:"grand_granchild2_2" 
                                } 
                            ] 
                        }, 
                    ] 
                } 
            ] 
        }; 
  
        var obj = d3.hierarchy(tree); 
  
        const BFS = []; 
          
        // Function is used 
        obj.each(d => BFS.push( 
            " ".repeat(d.depth) + `${d.depth}:${d.data.name}` 
            )); 
  
        BFS.forEach((e)=>{ 
            console.log("level:",e); 
        }); 
    </script>  
</body>  
  
</html>

輸出：

範例2：

HTML

<!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>  
    // Constructing a tree 
    var tree={ 
            // Level zero 
            name:"rootNode", 
            children:[ 
                { 
                    // Level one 
                    name:"child1" 
                }, 
                { 
                    // Level one 
                    name:"child2", 
                    children:[ 
                        { 
                            // Level two 
                            name:"grandchild1", 
                            children:[{ 
                                name:"grand_granchild1_1" 
                            }, 
                            { 
                                name:"grand_granchild1_2" 
                            }] 
                        } 
                    ] 
                }, 
                  
                { 
                    // Level one 
                    name:"child3" 
                }, 
                { 
                    // Level one 
                    name:"child4" 
                } 
            ] 
        }; 
  
        var obj = d3.hierarchy(tree); 
  
        const BFS = []; 
        
        // Function is used 
        obj.each(d => BFS.push( 
            " ".repeat(d.depth)  
                + `${d.depth}:${d.data.name}` 
        )); 
  
        console.log(BFS); 
    </script>  
</body>  
  
</html>

輸出：

相關用法

注：本文由純淨天空篩選整理自tarun007大神的英文原創作品 D3.js node.each() Function。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。