aspnetboilerplate AsyncCrudAppService 函数返回浏览器纯文本

如何解决aspnetboilerplate AsyncCrudAppService 函数返回浏览器纯文本

public class InteractionAppService : AsyncCrudAppService<Interaction,InteractionDto,long,PagedInteractionResultRequestDto,CreateInteractionDto,InteractionDto>,IInteractionAppService
{
    [HttpGet]
    public string DownloadTestFile2()
    {
        var fileCachePath = @"c:\CHAT\cache.txt";

        if (System.IO.File.Exists(fileCachePath) == true)
        {
            var fileCache = System.IO.File.ReadAllBytes(fileCachePath);
            return Encoding.ASCII.GetString(fileCache.ToArray());
        }

        return "test";
    }
}

上面的代码返回数组/json
我想返回网络浏览器纯文本。例如，测试我如何在 aspboilerplate 上做到这一点 在控制器上很容易，但我需要使用 service(AsyncCrudAppService)

{"result":"\nSTARTFILE\nfunction msg(){ \r\n alert("Hello CHAT"); \r\n} \r\n\r\nmsg();\nENDFILE \n\nSTARTFILE\n\r\n.btn-primary {\r\n 颜色：#fff；\r\n 背景颜色：#1b6ec2；\r\n 边框颜色：#1861ac；\r\n }\r\n\nENDFILE\n\nSTARTFILE\n{\r\n "chat": "1",\r\n "video": "2",\r\n "users": "3"\ r\n}\nENDFILE\n","targetUrl":null,"success":true,"error":null,"unAuthorizedRequest":false,"__abp":true}