我正在自学 javascript,但看起来我遇到了障碍。作为练习,我正在尝试构建一个税收计算器。
这是我构建的一个包含税级的对象:
var taxBracket = [
{bracket: 1, from:0, to:18200, percentage :0, amount:0},
{bracket: 2, from:18201, to:37000, percentage :19, over:18200, amount:0},
{bracket: 3, from:37001, to:80000, percentage :32.5, over:37000, amount:3752},
{bracket: 4, from:80001, to:180000, percentage :37, over:80000, amount:17547},
{bracket: 5, from:180001, to:0, percentage :45, over:180000, amount:54547}];
这是循环遍历对象以查找 y 相应税级的函数
function returnTax (y){
for(var x in taxBracket){
if (y >= taxBracket[x].from && y <= taxBracket[x].to){
var z = taxBracket[x].amount + ((grossIncome-taxBracket[x].over) * (taxBracket[x].percentage/100));
return z;
}
};
问题是,如果 y
超过 180000,则会出错,因为 to
为 0。这是唯一的解决方案吗?else 语句重复 if 的功能陈述?感谢您的帮助!
最佳答案
到目前为止,进展顺利。只需使用 Infinity 而不是在最后一个括号上默认为 0 即可修复此问题。我也对您的语法提出了一些建议,希望对您有所帮助。
var taxBracket = [
{bracket: 1, from: 0, to: 18200, percentage: 0, amount: 0},
{bracket: 2, from: 18201, to: 37000, percentage: 19, over: 18200, amount: 0},
{bracket: 3, from: 37001, to: 80000, percentage: 32.5, over: 37000, amount: 3752},
{bracket: 4, from: 80001, to: 180000, percentage: 37, over: 80000, amount: 17547},
// Use Infinity instead of 0 for the "to" value of bracket 5
{bracket: 5, from: 180001, to: Infinity, percentage: 45, over: 180000, amount: 54547}
];
// Variable names like 'x', 'y' and 'z' can cause problems with code readability.
// Descriptive names such as "income", or even "string" or "int" will help you out when you come to review your code later!
function returnTax(y){
// Using for..in with arrays can cause issues with enumerating over object properties.
// You don't have to worry about it in this case, but a standard for loop (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for) is better practice.
for(var x = 0; x < taxBracket.length; x++){
if(y <= taxBracket[x].to){
// I find breaking up long calculations into separate variables can make it
// more readable. More preference than anything else though!
var amountOver = grossIncome - taxBracket[x].over;
var percent = taxBracket[x].percentage / 100;
return taxBracket[x].amount + (amountOver * percent);
}
}
}
关于javascript - 尝试练习如何处理数组,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/25588561/