D3.js pie.value()函数

pie.value()函数用于设置饼图生成器函数返回的数据的 value 属性。如果指定了值，那么它将值设置为给定的动态或静态函数或数字。

句法：

pie.value([value]);

参数：此函数接受如上所述和下文所述的单个参数。

• value：此参数采用函数或数字。

返回值：此函数不返回任何内容。

示例 1：

HTML

  

    
    
  
    
    
    

  

    
        
            
                GeeksforGeeks
            
            
                pie.value()
            
            
                When given data array 
                consists objects
            
        
        
        
    
      
    
        // Data to be added in the pie chart
        var data = [
            { "value": 1, "property": "p1" },
            { "value": 2, "property": "p2" },
            { "value": 3, "property": "p3" },
            { "value": 4, "property": "p4" },
            { "value": 5, "property": "p5" },
            { "value": 6, "property": "p6" }
        ]
  
        // Selecting SVG using d3.select()
        var svg = d3.select("svg");
  
        // Creating Pie generator
        var pie = d3.pie()
            // Use of pie.value() Function
            .value((d) => { return d.value });
  
        // Creating arc
        var arc = d3.arc()
            .innerRadius(0)
            .outerRadius(100);
  
        let g = svg.append("g")
            .attr("transform", "translate(150, 120)");
  
        // Grouping different arcs
        var arcs = g.selectAll("arc")
            .data(pie(data))
            .enter()
            .append("g");
  
        // Appending path 
        arcs.append("path")
            .attr("fill", (data, i) => {
                return d3.schemeSet2[i];
            })
            .attr("d", arc);
    

  

输出：

示例 2：

HTML

  

    
    
    
    
    

  

    
        
            
                GeeksforGeeks
            
            
                pie.value()
            
            
                When given data array 
                consists objects
            
        
        
        
    
    
        // Data to be added in the pie chart
        var data = [
            { "value": 1, "property": "p1" },
            { "value": 2, "property": "p2" },
            { "value": 3, "property": "p3" },
            { "value": 4, "property": "p4" },
            { "value": 5, "property": "p5" },
            { "value": 6, "property": "p6" }
        ]
  
        // Selecting SVG using d3.select()
        var svg = d3.select("svg");
  
        // Creating Pie generator
        var pie = d3.pie()
            // Use of pie.value() Function
            .value((d) => { return d.value })
            (data);
  
        // Creating arc
        var arc = d3.arc()
            .innerRadius(50)
            .outerRadius(100);
  
        let g = svg.append("g")
            .attr("transform", "translate(150, 120)");
  
        // Grouping different arcs
        var arcs = g.selectAll("arc")
            .data(pie)
            .enter()
            .append("g");
  
        // Appending path 
        arcs.append("path")
            .attr("fill", (data, i) => {
                return d3.schemeSet2[i];
            })
            .attr("d", arc);
  
        arcs.append("text")
            .attr("transform", (d) => {
                return "translate(" +
                    arc.centroid(d) + ")";
            })
            .text(function (d) {
                return d.value;
            });
    

  

输出：