更改或覆盖响应错误请求消息web api c#

public class CustomException : Exception
{
    public CustomException(string message) : base(message)
    {
    }

    // 添加自定义属性和方法
}

public IHttpActionResult Get()
{
    try
    {
        // 处理请求
    }
    catch (Exception ex)
    {
        // 创建自定义异常对象
        var customException = new CustomException("自定义错误消息");

        // 抛出自定义异常
        throw customException;
    }
}

public class CustomExceptionFilterAttribute : ExceptionFilterAttribute
{
    public override void OnException(HttpActionExecutedContext actionExecutedContext)
    {
        if (actionExecutedContext.Exception is CustomException)
        {
            // 获取自定义异常对象
            var customException = (CustomException)actionExecutedContext.Exception;

            // 创建自定义错误响应消息
            var response = new HttpResponseMessage(HttpStatusCode.BadRequest)
            {
                Content = new StringContent(customException.Message),
                ReasonPhrase = "自定义错误原因"
            };

            // 替换响应消息
            actionExecutedContext.Response = response;
        }
    }
}

public static class WebApiConfig
{
    public static void Register(HttpConfiguration config)
    {
        // 注册全局异常过滤器
        config.Filters.Add(new CustomExceptionFilterAttribute());

        // 其他配置...
    }
}