//接口返回自动转小写，容易造成前后端不一致，获取不到数据，切换成转驼峰（首字母大写）如Code/Result
//在ConfigureServices中配置
services.AddMvc().AddJsonOptions(options => { options.SerializerSettings.ContractResolver = new DefaultContractResolver(); }).SetCompatibilityVersion(CompatibilityVersion.Version_2_2);