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c#asp.netvalidationtextboxmaxlength

How reliable is the MaxLength property of the TextBox-Control?

The TextBox control offers a MaxLength property, which allows the insertable text into that TextBox be clientside limited to the specified amount of chars.

My questions:

  • Is this property only client-side and therefore browser-pedendent?
  • Can I rely on the fact, that the Text property contains no text longer than MaxLength is set (only for the DisplayModes named in the MSDN article) or do I manually have to perform a TextBox.Text.SubString(0, DesiredMaxLength) ?
  • How does all this behave with disabled java-script?
Solution

  • It does not depend on javascript but that does not make it safe.

    Anyone can still post a request using javascript (XmlHttpRequest for example) or just craft a request to send more data than the max-length specification. It's a good way to stop a normal user from over populating a field but it is something you need to double check on the server anyway.