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Telerik.Web.UI.CaptchaImage

RadCaptcha image generation class

Inheritance Hierarchy

  • System.Object
  • Telerik.Web.UI.CaptchaImage

Properties

AudioFilesPath String

Gets or sets the path to the directory where the audio (.wav) files are located.
The default value is ~/App_Data/RadCaptcha.

Remarks

Use the AudioFilesPath property to specify the directory where the audio (*.wav) files are located, and from which the
audio code is generated. The audio files must be named "[Char]".wav (i.e. A.wav, B.wav, C.wav, 1.wav, 2.wav) and should contain the audio that
corresponds to the specific character. Place the RadCaptcha folder (provided with the installation) in the App_Data directory of your WebSite.

BackgroundColor Color

Gets or sets the background color of the CaptchaImage.

BackgroundNoise CaptchaBackgroundNoiseLevel

Gets or sets the amount of background noise to generate in the RadCaptcha image.

CharSet String

Gets or sets a custom Character Set, from which the characters
used to render RadCaptcha, are randomly chosen. The TextChars property must be set to CustomCharSet.

EnableAudioNoise Boolean

Gets or sets a boolean value indicating whether a noise should be added to the CaptchaAudio.

EnableCaptchaAudio Boolean

Gets or sets the bool value indicating whether the CaptchaAudio will be enabled.

FontFamily String

Gets or sets the font used to render RadCaptcha text.

FontWarp CaptchaFontWarpFactor

Gets or sets the amount of random font warping used on the RadCaptcha text.

FontWhitelist String

Gets or sets a semicolon-delimited list of valid fonts to use when no font is provided.

Height Int32

Gets or sets the height of the RadCaptcha image.

ImageAlternativeText String

Gets or sets the RadCaptcha image alternative text.

ImageCssClass String

Gets or sets the RadCaptcha image CSS class.

LineNoise CaptchaLineNoiseLevel

Gets or sets the line noise level to the RadCaptcha image.

PersistCodeDuringAjax Boolean

Gets or sets a bool value that indicates whether or not the Captcha will persist the code during Ajax requests that do not affect
the RadCaptcha control. The default is false, which means a new code will be generated on every trip to the server (no matter if full or partial postback).
Note: This property is useful when there is another Ajax panel on the page that does not update the Captcha. Setting it to true will cause the RadCaptcha control to persist its code during the Ajax requests.

PreviousText String

Gets the previous text of the CaptchaImage.

RenderedAt DateTime

Gets the date and time this image was last rendered

RenderImageOnly Boolean

Gets or sets bool value that indicates
whether the RadCaptcha Image will only be rendered on the page (without the textbox and Label).

Text String

Gets the randomly generated RadCaptcha text.

TextChars CaptchaPossibleChars

Gets or sets the characters used to render RadCaptcha text.
A character will be picked randomly from the string.

TextColor Color

Gets or sets the color of the RadCaptcha text.

TextLength Int32

Gets or sets the number of CaptchaChars used in the RadCaptcha text.

UniqueId String

Gets a GUID that uniquely identifies this CaptchaImage

UseAudioFiles Boolean

Gets or sets a bool value indicating whether the audio code will be generated by concatenation of the audio files from a given folder.

UseRandomFont Boolean

Gets or sets a bool value indicating
whether a random font will be used to generate the CaptchaImage text.

Width Int32

Gets or sets the width of the RadCaptcha image.

Methods

AddLine

Add variable level of curved lines to the image

Returns

System.Void

AddNoise

Add a variable level of graphic noise to the image.

Returns

System.Void

GenerateCode

Generates a new RadCaptcha code.

Parameters

filterWords System.Boolean

Bool value that indicates whether or not bad words will be filtered.
RadCaptcha has a built-in list of words that should not appear on the image.

Returns

System.Void

GenerateCode

Generates a new RadCaptcha code.

Returns

System.Void

GenerateImagePrivate

Renders the RadCaptcha image.

Returns

System.Drawing.Bitmap

GenerateRandomText

Generates random text for the RadCaptcha.

Returns

System.String

GetFont

Returns the RadCaptcha font in an appropriate size.

Returns

System.Drawing.Font

IsOffensiveWord

Checks whether the current code is an offensive word.

Returns

System.Boolean True if the word is offensive.

RandomFontFamily

Returns a random font family from the font whitelist

Returns

System.String

RandomPoint

Returns a random point within the specified x and y ranges.

Returns

System.Drawing.PointF

RandomPoint

Returns a random point within the specified rectangle.

Returns

System.Drawing.PointF

RenderImage

Forces a new Captcha image to be generated using current property value settings.

Returns

System.Drawing.Bitmap

TextPath

Returns a GraphicsPath containing the specified string and font.

Returns

System.Drawing.Drawing2D.GraphicsPath

WarpText

Warps the provided text GraphicsPath by a variable amount.

Returns

System.Void