selectAll:function(){
            let that=this;
	    //console.log(that.url.getAll)
	    uni.request({
	    method:'POST',
	    url: that.url.getAll, //仅为示例，并非真实接口地址。
	    data:{},
	    success: (res) => {
	    console.log(res.data);
	    that.book=res.data.list			
	this.text = 'request success';
	}
    })
}

因为复制代码的时候，只会复制uni.request里的全部东西，所以错过了:

let that=this;

所以导致报错