個稅計算器 / 微信小程序開發

2019年1月1日即將到來，碼農們除了關心自己的技能之外，還有薪資是不是可以多拿點。 每次算的時候 都要百度一下個人所得稅，但是很多都是老的稅率計算，找一個新的出來還是比較麻煩，所以個人開發了一個最新稅率的小程序。解決和我有着一樣痛苦的碼農們的問題。

根據最新稅改後計算個人所得稅的計算器。目前支持南京，後續開放 杭州 上海 北京等城市。 如果有疑問的可以加最下方 開發者微信。

• 首先在微信官網下載微信小程序開發工具 https://mp.weixin.qq.com
• 在https://mp.weixin.qq.com 註冊小程序賬號，完成個人實名認證。
• 在小程序後臺拿到appid，下面就可以開發了。

實例查看二維碼：

先使用weui 小程序ui框架就行頁面佈局

<button block type="dark" bindtap='calculationBindtap'>計算</button>

其次寫JS代碼（計算按鈕邏輯代碼）

import data from './data'

const app = getApp;

Page({
    data: {
        options1: data,
        value: '1',
        checked: true,
        standard: 1,
        marking: 5000,
        beforetaxCount: 0,
        specialitemCount: 0
    },
    

    calculationBindtap:function(){
        // 開始計算  計算完成把計算結果放在result對象中
        var beforetaxCount = this.data.beforetaxCount;
        var specialitemCount = this.data.specialitemCount;
        var marking = this.data.marking;
        if (beforetaxCount == null || beforetaxCount == 0 || beforetaxCount == ''){
            wx.showToast({
                title: '輸入正確薪資',
                mask: true,
                icon: 'loading'
            })
            return;
        }
        if (specialitemCount == null || specialitemCount == ''){
            specialitemCount = 0;
        }
        // 開始計算

        var oldNum = 0.08;
        var medNum = 0.02;
        var unemNum = 0.005;
        var workNum = 0;
        var giveNum = 0;

        var providentfundNum = 0.08;

        var insuranceBase = 19935;
        var providentfundBase = 25300;

        var oldcount = 0;
        var medcount = 0;
        var unemcount = 0;
        var workcount = 0;
        var givecount = 0;

        var providentfundcount = 0;

        var privateFee = 0;
        var plusFee = 0;

        if(this.data.checked){
            if (parseFloat(beforetaxCount) > parseFloat(insuranceBase)) {
                oldcount = parseFloat(insuranceBase) * parseFloat(oldNum);
                medcount = parseFloat(insuranceBase) * parseFloat(medNum);
                unemcount = parseFloat(insuranceBase) * parseFloat(unemNum);
                workcount = parseFloat(insuranceBase) * parseFloat(workNum);
                givecount = parseFloat(insuranceBase) * parseFloat(giveNum);
            } else {
                oldcount = parseFloat(beforetaxCount) * parseFloat(oldNum);
                medcount = parseFloat(beforetaxCount) * parseFloat(medNum);
                unemcount = parseFloat(beforetaxCount) * parseFloat(unemNum);
                workcount = parseFloat(beforetaxCount) * parseFloat(workNum);
                givecount = parseFloat(beforetaxCount) * parseFloat(giveNum);
            }

            if (parseFloat(beforetaxCount) > parseFloat(providentfundBase)) {
                providentfundcount = parseFloat(providentfundBase) * parseFloat(providentfundNum);
            } else {
                providentfundcount = parseFloat(beforetaxCount) * parseFloat(providentfundNum);
            }
        }

        // 保險總費用
        var totalInsuranceFee = parseFloat(oldcount) + parseFloat(medcount) + parseFloat(unemcount) + parseFloat(workcount) + parseFloat(givecount);
        // 公積金費用 
        var totalProvidentfundFee = providentfundcount;

        // 下面的錢 交稅
        console.log(this.data.marking);
        var otherFee = parseFloat(beforetaxCount) - parseFloat(totalInsuranceFee) - parseFloat(totalProvidentfundFee) - parseFloat(this.data.marking) - parseFloat(specialitemCount);
        
        if (parseFloat(otherFee) <= 3000 && parseFloat(otherFee) > 0) {
            privateFee = parseFloat(otherFee) * 0.03;
            plusFee = 0;
        }
        if (parseFloat(otherFee) <= 12000 && parseFloat(otherFee) > 3000) {
            privateFee = parseFloat(otherFee) * 0.1;
            plusFee = 210;
        }
        if (parseFloat(otherFee) <= 25000 && parseFloat(otherFee) > 12000) {
            privateFee = parseFloat(otherFee) * 0.2;
            plusFee = 1410;
        }
        if (parseFloat(otherFee) <= 35000 && parseFloat(otherFee) > 25000) {
            privateFee = parseFloat(otherFee) * 0.25;
            plusFee = 2660;
        }
        if (parseFloat(otherFee) <= 55000 && parseFloat(otherFee) > 35000) {
            privateFee = parseFloat(otherFee) * 0.3;
            plusFee = 4410;
        }
        if (parseFloat(otherFee) <= 80000 && parseFloat(otherFee) > 55000) {
            privateFee = parseFloat(otherFee) * 0.35;
            plusFee = 7160;
        }
        if ( parseFloat(otherFee) > 80000) {
            privateFee = parseFloat(otherFee) * 0.45;
            plusFee = 15160;
        }

        var result = {};
        
        result.insuranceCount = totalInsuranceFee;
        result.providentfundCount = totalProvidentfundFee;
        result.providentfundNum = parseFloat(providentfundNum) * 100;
        result.money = parseFloat(beforetaxCount) - parseFloat(totalInsuranceFee) - parseFloat(totalProvidentfundFee) - parseFloat(privateFee) + parseFloat(plusFee);
        result.privateFee = privateFee - parseFloat(plusFee);
        result.specialitemCount = specialitemCount;
        result.oldNum = parseFloat(oldNum) * 100;
        result.medNum = parseFloat(medNum) * 100;
        result.unemNum = parseFloat(unemNum) * 100;
        result.workNum = parseFloat(workNum) * 100;
        result.giveNum = parseFloat(giveNum) * 100;

        result.oldcount = parseFloat(oldcount);
        result.medcount = parseFloat(medcount);
        result.unemcount = parseFloat(unemcount);
        result.workcount = parseFloat(workcount);
        result.givecount = parseFloat(givecount);

        wx.setStorage({
            key: 'result',
            data: result,
            success:function(){
                wx.navigateTo({
                    url: '../calculation/calculationResult',
                })
            }
        })
        
    },

})

把計算好的結果放在result對象中 通過wx.setStorage 放在緩存中，傳到下一個頁面。最後展示出來。