vue实现后端文件下载到当前浏览器

比如现在在后端生成一个.sql文件并下载到当前浏览器：比如我的后端接口是localhost:8087/user/userController/exportSql，

前端地址是localhost:9095/user#。

一、前端：

<el-button @click="getSql()">导出</el-button>

var url = process.env.BASE_API
url += '/userController/exportSql?userId=' + userId
window.open(url)

注意这里url不能是/user/userController/expoerSql，因为window.open，会把/当成前端的页面地址，而不是后端。 

二、后端：

/**
	 * 导出SQL
	 */
    @ResponseBody
	@RequestMapping("/exportSql")
	public HttpResult exportSql(String userId,HttpServletResponse response){
		try {
			
			response.reset();
		    response.setContentType("text/plain");  
	        response.addHeader("Content-Disposition",  
	                "attachment;filename=测试user.sql");
	        BufferedOutputStream buff = null;  
	        StringBuffer write = new StringBuffer();  
	        String enter = "\r\n";  
	        ServletOutputStream outSTr = null;  
	        try {  
	            outSTr = response.getOutputStream();
	            buff = new BufferedOutputStream(outSTr);  
	            //拼接SQL
	            write.append("内容为"+userId);	      
	            buff.write(write.toString().getBytes("UTF-8"));  
	            buff.flush();  
	            buff.close();  
	        } catch (Exception e) {  
	            e.printStackTrace();  
	        } finally {  
	            try {  
	                buff.close();  
	                outSTr.close();  
	            } catch (Exception e) {  
	                e.printStackTrace();  
	            }  
	        }  
	        
			return HttpResult.getSuccessInstance();
		} catch (Exception e) {
			logger.error("导出SQL：" + e.getMessage(), e);
			return HttpResult.getFailedInstance("生成SQL失败");
		}
		
	}
}

　　如果是视频，修改为：

response.setContentType("video/mpeg4");
            response.addHeader("Content-Disposition",
                    "attachment;filename="+ossResourcesInfo.getName());　　

如果要显示文件大小和预计时长，加上下面这段逻辑

InputStream inputStream = urlConnection.getInputStream();
 response.setHeader("Content-Length", ""+contentLength);

　　

原文：https://blog.csdn.net/w_t_y_y/article/details/95603361