/// <summary>
/// 是否开始使用验证码
/// </summary>
/// <param name="userName">用户名</param>
/// <param name="scenarios">验证码使用场景</param>
/// <returns></returns>
public static bool UseCaptcha(VerifyScenarios scenarios = VerifyScenarios.Post, bool isLimitCount = false)
{
CaptchaSettings verificationCodeSettings = CaptchaSettings.Instance();
if (!verificationCodeSettings.EnableCaptcha)
{
return(false);
}
IUser currentUser = UserContext.CurrentUser;
if (scenarios == VerifyScenarios.Register || currentUser == null && scenarios == VerifyScenarios.Post)
{
return(true);
}
//后台登陆
if (scenarios == VerifyScenarios.Login && currentUser != null)
{
return(true);
}
if (currentUser == null && scenarios == VerifyScenarios.Post && verificationCodeSettings.EnableAnonymousCaptcha)
{
return(true);
}
string userName = GetUserName();
if (scenarios == VerifyScenarios.Login && UserIdToUserNameDictionary.GetUserId(userName) == 0)
{
return(false);
}
string cacheKey = GetCacheKey_LimitTryCount(userName, scenarios);
int? limitTryCount = cacheService.Get(cacheKey) as int?;
if (limitTryCount.HasValue &&
((scenarios == VerifyScenarios.Login && limitTryCount >= verificationCodeSettings.CaptchaLoginCount) ||
(scenarios == VerifyScenarios.Post && limitTryCount >= verificationCodeSettings.CaptchaPostCount)))
{
return(true);
}
if (isLimitCount)
{
if (limitTryCount.HasValue)
{
limitTryCount++;
}
else
{
limitTryCount = 1;
}
cacheService.Set(cacheKey, limitTryCount, CachingExpirationType.SingleObject);
}
return(false);
}
public void ProcessRequest(HttpContext context)
{
HttpContextBase currentContext = new HttpContextWrapper(context);
bool isremove = false;
if (!string.IsNullOrEmpty(context.Request.QueryString["isremove"]))
{
bool.TryParse(context.Request.QueryString["isremove"], out isremove);
}
string cookieName = CaptchaSettings.Instance().CaptchaCookieName;
bool enableLineNoise = CaptchaSettings.Instance().EnableLineNoise;
CaptchaCharacterSet characterSet = CaptchaSettings.Instance().CharacterSet;
int minCharacterCount = CaptchaSettings.Instance().MinCharacterCount;
int maxCharacterCount = CaptchaSettings.Instance().MaxCharacterCount;
string generatedKey = string.Empty;
bool addCooikes = false;
//创建或从缓存取验证码
string key = null;
if (context.Request.Cookies[cookieName] != null)
{
key = context.Request.Cookies[cookieName].Value;
}
if (isremove && !string.IsNullOrEmpty(key))
{
VerificationCodeManager.GetCachedTextAndForceExpire(currentContext, getCurrentLevelKey(key));
}
System.IO.MemoryStream ms = null;
if (!string.IsNullOrEmpty(key))
{
ms = VerificationCodeManager.GetCachedImageStream(getCurrentLevelKey(key));
}
if (ms == null)
{
Size size = new Size(85, 30);
VerificationCodeImage image = VerificationCodeManager.GenerateAndCacheImage(currentContext, size, 300, out generatedKey, characterSet, enableLineNoise, minCharacterCount, maxCharacterCount);
ms = VerificationCodeManager.GetCachedImageStream(getCurrentLevelKey(generatedKey));
VerificationCodeManager.CacheText(currentContext, image.Text, getCurrentLevelKey(generatedKey), false, 300);
addCooikes = true;
}
if (addCooikes)
{
HttpCookie cookie = new HttpCookie(cookieName, generatedKey);
context.Response.Cookies.Add(cookie);
}
context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
context.Response.ContentType = "image/Jpeg";
context.Response.BinaryWrite(ms.ToArray());
//context.Response.Flush();
context.Response.End();
}
/// <summary>
/// 验证码是否输入正确
/// </summary>
/// <param name="filterContext"></param>
/// <returns></returns>
public bool IsCaptchaValid(ActionExecutingContext filterContext)
{
ControllerBase controllerBase = filterContext.Controller;
string captchaText = controllerBase.ControllerContext.HttpContext.Request.Form[_captchaInputName];
if (string.IsNullOrEmpty(captchaText))
{
return(false);
}
string cookieName = CaptchaSettings.Instance().CaptchaCookieName;
HttpCookie coookie = filterContext.HttpContext.Request.Cookies[cookieName];
string cookieCaptcha = string.Empty;
if (coookie != null)
{
if (!string.IsNullOrEmpty(coookie.Value))
{
try
{
cookieCaptcha = VerificationCodeManager.GetCachedTextAndForceExpire(filterContext.HttpContext, coookie.Value);
}
catch { }
}
}
//从cookie未获取验证码时，提供一个随机数
if (cookieCaptcha == null)
{
cookieCaptcha = DateTime.UtcNow.Ticks.ToString();
}
if (!string.IsNullOrEmpty(captchaText) &&
!captchaText.Equals(cookieCaptcha, StringComparison.CurrentCultureIgnoreCase))
{
return(false);
}
return(true);
}