Impossible to use the attributes StringValidator/RegexValidator to ensure length of string

  • Thread starter =?iso-8859-1?Q?Gabriel_Lozano-Mor=E1n?=
  • Start date


When creating your own configuration section it's not possible to enforce a specific length for a specific property.


1: public class CryptoSection : ConfigurationSection 2: { 3: #region Construction 4: 5: public CryptoSection() 6: { 7: } 8: 9: #endregion 10: 11: #region Properties 12: 13: [ConfigurationProperty("decryptionKey", IsRequired = true, IsKey = false)] 14: [StringValidator(MinLength = 24, MaxLength = 24)] 15: public string DecryptionKey 16: { 17: get 18: { 19: return (string) this["decryptionKey"]; 20: } 21: set 22: { 23: this["decryptionKey"] = value; 24: } 25: } 26: 27: #endregion 28: }
Then calling the following lines will throw an exception because for some reason when the validator gets invoked the first time this["decryptionKey"] will always be "" and therefore a length of 0:

1: CryptoSection cs = ConfigurationManager.GetSection("cryptoSection") as CryptoSection; 2: Response.Write("DecryptionKey = " + cs.DecryptionKey);
The exception being thrown is:

ArgumentException: The string must be at least 24 characters long.]
System.Configuration.StringValidator.Validate(Object value) +247
System.Configuration.ConfigurationProperty.Validate(Object value) +27

[ConfigurationErrorsException: The value for the property 'decryptionKey' is not valid. The error is: The string must be at least 24 characters long.]
System.Configuration.BaseConfigurationRecord.CallCreateSection(Boolean inputIsTrusted, FactoryRecord factoryRecord, SectionRecord sectionRecord, Object parentConfig, ConfigXmlReader reader, String filename, Int32 line) +276

The only work-around i have found so far is by setting in the ConfigurationPropertyAttribute a default value with a length of 24 (Eg: 24 spaces), no need. There has to be a better way otherwise the the MinLength of the StringValidator is useless in this context because the value will always be a String.Empty when the validator is invoked.

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question