axios download files directly

1. Axios request needs to set responseType: "blob"

2. Follow the request to read as follows (the following is the sample code). 

let data = {
    screenProjectDto: JSON.stringify(param),
    countName: "项目列表",
    rowsName: rowsName.join(","),
    order: _this.sorter.order,
    prop: _this.sorter.prop
};
const res = await exportPostApi(data);
const blob = res;
const reader = new FileReader();
reader.readAsDataURL(blob);
reader.onload = (e) => {
const a = document.createElement('a');
a.download = `项目列表.xls`;
a.href = e.target.result;
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
}