一：定义需要放大缩小的模块

<template>
  <view class="container">
      <view id="content" class="content" @touchstart="onTouchStart" @touchmove="onTouchMove" @touchend="onTouchEnd"
      :style="{'transform-origin':`${originX}px ${originY}px` ,'transform': `scale(${lastScale})`}">
          <view>文本内容</view>
      </view>
  </view>
</template>

<style>
.container {
    width: 100%;
    height: 100vh;
    overflow: auto;
}

.content {
    width: 100%;
    height: 100%;
    background-color: #eee;
    transition: transform 0.3s;
}
</style>

二：处理相关事件

<script>
export default {
  data() {
      return {
          originX: 0,
          originY: 0,
          lastDistance: 0,
          lastScale: 1,
      };
  },
  methods: {
      onTouchStart(event) {
          if (event.touches.length === 2) {
              const point1 = event.touches[0];
              const point2 = event.touches[1];
              this.lastDistance = this.getDistance(point1, point2);
      
              const query = wx.createSelectorQuery();
              query.select('#content').boundingClientRect((rect) => {
                  this.originX = (point1.clientX + point2.clientX) / 2 - rect.left;
                  this.originY = (point1.clientY + point2.clientY) / 2 - rect.top;
              }).exec();
          }
      },
      onTouchMove(event) {
          if (event.touches.length === 2) {
              const point1 = event.touches[0];
              const point2 = event.touches[1];
              const distance = this.getDistance(point1, point2);
              const scale = distance / this.lastDistance;
              this.lastDistance = distance;
              this.lastScale *= scale;
	      if(this.lastScale < 1){
	      	  this.lastScale = 1
	      }
          }
      },  
      onTouchEnd() {
          this.lastDistance = 0;
          this.lastScale = 1;
      },
      getDistance(point1, point2) {
          const x = point2.clientX - point1.clientX;
          const y = point2.clientY - point1.clientY;
          return Math.sqrt(x * x + y * y);
      },
  },  
};
</script>