void main() { double toly = bmi(weight: 70, height: 1.8); double ls = bmi(height: 1.79); double wy = bmi(height: 1.69, weight: 50); print("===toly:$toly===ls:$ls===wy:$wy==="); } // void main() { // double toly = 1.8 / (70 * 70); // double ls = 1.79 / (65 * 65); // double wy = 1.69 / (50 * 50); // print("===toly:$toly===ls:$ls===wy:$wy==="); // } double bmi({ required double height, double weight = 65, }) { // 具体算法 double result = weight / (height * height); return result; }