定义：bodyArr: Array = []
被调用的函数
bodyCheck() {
if (this.bodyArr.length <= 0) return;
if (this.eatBean >= this.bodyBeanNum && this.bodyArr.length < this.bodyMaxNum) {
let addBodyNum = Math.floor(this.eatBean / this.bodyBeanNum)
let x = this.bodyArr[this.bodyArr.length - 1].x
。。。。。。
}
let x = this.bodyArr[this.bodyArr.length - 1].x 这一句报错
