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This class can be used to initiate a spell check request using the RadSpell dictionaries.

Inheritance Hierarchy

  • System.Object
  • Telerik.Web.UI.SpellChecker : IDisposable


CheckAllCaps Boolean

Specifies whether or not to check words in CAPITALS (e.g. "UNESCO")

CheckCapital Boolean

Specifies whether or not to check words in Capitals (e.g. "Washington")

CheckForRepeatWords Boolean

Specifies whether or not to count repeating words as errors (e.g. "very very")

CheckWordsWNumbers Boolean

Specifies whether or not to check words containing numbers (e.g. "l8r")

CustomAppendix String

The suffix that gets appended to the custom dictionary file name. It is usually a user specific string that allows to distinguish dictionaries for different users. Default filenames are Language + CustomAppendix + ".txt". The default is -Custom

CustomDictionarySource ICustomDictionarySource

Manipulate the custom dictionary source. The new value must implement ICustomDictionarySource.

CustomDictionarySourceType ICustomDictionarySource

The fully qualified name of the type that will be used for the custom dictionary storage. The type name must include the assembly, culture and public key token. A new instance will be created internally unless you set CustomDictionarySource directly.

DictionaryLanguage String

The language of the dictionary to be used for spellchecking. It usually is the same as the corresponding TDF file (without the extension).


To spellcheck in German you have to have de-DE.tdf inside your dictionary folder, and set DictionaryLanguage to "de-DE" C#:

        spellChecker.DictionaryLanguage = "de-DE";


        spellChecker.DictionaryLanguage = "de-DE"

DictionaryPath String

The folder path that contains the TDF files.


The method expects local paths. E.g. "C:\SomeFolder\RadControls\Spell\TDF". Transform URL's to local paths with the method. C#

        SpellChecker checker = new SpellChecker(Server.MapPath("~/RadControls/Spell/TDF"));


        Dim checker As SpellChecker
           checker = New SpellChecker(Server.MapPath("~/RadControls/Spell/TDF"))

EditDistance Int32

Specifies the edit distance. If you increase the value, the checking speed decreases but more suggestions are presented. It does not do anything for the phonetic spellchecking.

Errors SpellCheckErrors

The errors after the last spellcheck. The getter method will call automatically if the text has not been checked yet.

FragmentIgnoreOptions FragmentIgnoreOptions

Configures the spellchecker engine, so that it knows whether to skip URL's, email addresses, and filenames and not flag them as erros.

SpellCheckProvider SpellCheckProvider

Specifies whether RadSpell should use the internal spellchecking algorithm or try to use Microsoft Word. The possible values are defined in the enum.

SpellCheckProviderTypeName String

Specifies the type name for the custom spell check provider

Text String

Sets the text to be spellchecked. It can be plain text or HTML.


This property can be used to pass the text to the spellchecker engine programmatically. The engine can deal with plaintext or any HTML-like format. It ignores text inside angle brackets (<>) and transforms HTML entities to their character values. E.g. & becomes & C#:

        using (SpellChecker checker = new SpellChecker(Server.MapPath("~/RadControls/Spell/TDF")))
            checker.Text = text;
            return checker.Errors;


        Dim checker As SpellChecker
            checker = New SpellChecker(Server.MapPath("~/RadControls/Spell/TDF"))
            checker.Text = text
            Return checker.Errors
        End Try

TextWords String

This property returns the list of words that was generated when the property is set.

WordIgnoreOptions WordIgnoreOptions

A set of rules that specify words that should be ignored during the spellcheck. Note that this property should be set before the property.



Adds a new word to the custom dictionary. It first checks if the word is already present in the current base or custom dictionaries.


word System.String

The new custom word.




Performs the actual spellchecking. It will be automatically called by the Errors property accessor.


Telerik.Web.UI.SpellCheckErrors -- a collection with all the errors found.


Cleans up any resources held by the SpellChecker object. It is an alias of the Dispose method.




Clean up used resources.




Gets a list of suggestions from the dictionary for the specified word


word System.String

A string containing the word to be used.


System.String[] A string array containing the spellcheck suggestions for the input word.

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