基于微信小程序开发校园二手商城

1. 首先，在app.json文件中配置页面路径和窗口样式：
```json
{
  "pages": [
    "pages/index/index",
    "pages/logs/logs"
  ],
  "window": {
    "backgroundTextStyle": "light",
    "navigationBarBackgroundColor": "#fff",
    "navigationBarTitleText": "校园二手商城",
    "navigationBarTextStyle": "black"
  }
}
```
2. 在pages文件夹下创建index和logs两个文件夹，并在每个文件夹下创建对应的js、wxml、wxss文件。
3. 编写index.wxml文件：
```html
<view class="container">
  <view class="title">欢迎来到校园二手商城</view>
  <view class="search-bar">
    <input class="search-input" placeholder="搜索商品" bindinput="onSearchInput" />
  </view>
  <view class="goods-list">
    <block wx:for="{{goodsList}}" wx:key="id">
      <view class="goods-item">
        <image src="{{item.imgUrl}}" mode="aspectFit" class="goods-img" />
        <view class="goods-info">
          <view class="goods-name">{{item.name}}</view>
          <view class="goods-price">￥{{item.price}}</view>
          <button class="goods-btn" bindtap="onBuyClick">购买</button>
        </view>
      </view>
    </block>
  </view>
</view>
```
4. 编写index.wxss文件：
```css
.container {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20rpx;
}
.title {
  font-size: 36rpx;
  font-weight: bold;
  margin-bottom: 60rpx;
}
.search-bar {
  width: 100%;
  margin-bottom: 40rpx;
}
.search-input {
  width: 100%;
  height: 80rpx;
  padding: 0 20rpx;
  border: 1rpx solid #ccc;
  border-radius: 10rpx;
}
.goods-list {
  width: 100%;
}
.goods-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 30rpx;
}
.goods-img {
  width: 150rpx;
  height: 150rpx;
  border-radius: 50%;
}
.goods-info {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}
.goods-name {
  font-size: 28rpx;
  font-weight: bold;
  margin-bottom: 10rpx;
}
.goods-price {
  font-size: 24rpx;
  color: #f00;
}
.goods-btn {
  width: 100%;
  height: 60rpx;
  line-height: 60rpx;
  background-color: #f00;
  color: #fff;
  text-align: center;
  border-radius: 10rpx;
}
```
5. 编写index.js文件：
```javascript
Page({
  data: {
    goodsList: []
  },
  onSearchInput: function (e) {
    console.log('搜索关键词：', e.detail.value);
    // 根据搜索关键词获取商品列表，并更新data中的goodsList
  },
  onBuyClick: function (e) {
    console.log('购买按钮被点击');
    // 处理购买逻辑，例如跳转到支付页面
  }
});
```
6. 编写logs.wxml、wxss和js文件，可以参考index文件进行编写。
7. 最后，在app.json文件中添加logs页面路径：
```json
{
  "pages": [
    "pages/index/index",
    "pages/logs/logs"
  ]
}
```