帮我写一个房贷计算器得微信小程序

当然可以帮您写一个房贷计算器的微信小程序。下面是一个简单的示例代码：

//app.js
App({
  globalData: {
    loanAmount: 0,
    loanTerm: 0,
    interestRate: 0,
    monthlyPayment: 0
  },
  calculateMonthlyPayment: function () {
    const loanAmount = this.globalData.loanAmount;
    const loanTerm = this.globalData.loanTerm;
    const interestRate = this.globalData.interestRate;

    const monthlyInterestRate = interestRate / 100 / 12;
    const months = loanTerm * 12;
    const numerator = loanAmount * monthlyInterestRate;
    const denominator = 1 - Math.pow(1 + monthlyInterestRate, -months);

    const monthlyPayment = numerator / denominator;
    this.globalData.monthlyPayment = monthlyPayment.toFixed(2);
  }
})

<!-- pages/index/index.wxml -->
<view class="container">
  <view class="input-group">
    <text>贷款金额：</text>
    <input type="number" bindinput="onLoanAmountChange" placeholder="请输入贷款金额"></input>
  </view>
  <view class="input-group">
    <text>贷款年限：</text>
    <input type="number" bindinput="onLoanTermChange" placeholder="请输入贷款年限"></input>
  </view>
  <view class="input-group">
    <text>贷款利率：</text>
    <input type="number" bindinput="onInterestRateChange" placeholder="请输入贷款利率"></input>
  </view>
  <button bindtap="calculateMonthlyPayment">计算月供</button>
  <view class="result">
    <text>月供金额：</text>
    <text>{{monthlyPayment}}</text>
  </view>
</view>

// pages/index/index.js
const app = getApp();

Page({
  data: {
    monthlyPayment: 0
  },
  onLoanAmountChange: function (e) {
    app.globalData.loanAmount = parseInt(e.detail.value);
  },
  onLoanTermChange: function (e) {
    app.globalData.loanTerm = parseInt(e.detail.value);
  },
  onInterestRateChange: function (e) {
    app.globalData.interestRate = parseFloat(e.detail.value);
  },
  calculateMonthlyPayment: function () {
    app.calculateMonthlyPayment();
    this.setData({
      monthlyPayment: app.globalData.monthlyPayment
    });
  }
})

请注意，这只是一个简单的示例，可能不包含所有的房贷计算逻辑和输入验证。您可以根据自己的需求进行修改和扩展。同时，还需要为小程序添加相应的样式文件来美化界面。

希望这个示例能帮到您