2024-08-06 Javascript 使用 reduce 方法
寫法演進
.for 廻圈寫法
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| var data_pie = [ { CO2e_percentage: 10 }, { CO2e_percentage: 20 }, { CO2e_percentage: 30 }, ];
var totalPie = 0; for (var i = 0; i < data_pie.length; i++) { totalPie += data_pie[i].CO2e_percentage; }
console.log(totalPie);
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.ES5 寫法
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| var data_pie = [ { CO2e_percentage: 10 }, { CO2e_percentage: 20 }, { CO2e_percentage: 30 }, ];
var totalPie = data_pie.reduce(function(acc, row) { return acc + row.CO2e_percentage; }, 0);
console.log(totalPie);
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.ES6寫法
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| var data_pie = [ { CO2e_percentage: 10 }, { CO2e_percentage: 20 }, { CO2e_percentage: 30 }, ]; const totalPie = data_pie.reduce((acc, row) => acc + row.CO2e_percentage, 0);
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