Custom Validator Controls. 2

[Kalisto]

I have a custom validator that I want to use to check the length of a password (minimum of 4 caracters)

my html is

<asp:CustomValidator id="cvPasswordLength" 
runat="server" ErrorMessage="Password Must be at Least 4 Characters Long" ControlToValidate="tbPassword"
OnServerValidate="ServerValidatorPWLength">*</asp:CustomValidator>

But my code behind validator is never called.
This is the code that sets up the call

this.cvPasswordLength.ServerValidate += new System.Web.UI.WebControls.ServerValidateEventHandler(this.ServerValidatorPWLength);

Is there anything obviously wrong there?

(I intend adding in Client Side Validation as well, but want to get the server side working 1st)

 

[crazyboybert]

Unless your doing this just to try out custom validators I'd use a regular expression validator this...

<asp:regularexpressionvalidator id="val" runat="server" validationexpression="^[\w\d]{4,}$" ErrorMessage="Password Must be at Least 4 Characters Long" ControlToValidate="tbPassword" />

HTH

Rob


Go placidly amidst the noise and haste, and remember what peace there may be in silence - Erhmann 1927

 

[Kalisto]

Cheers, that would work for 1 thing i need to do, but i also want to check for invalid characters such as :/\<> etc, you'd recommend a regular expression for that as well?

 

[BoulderBum]

I'll call it "open source" I've been wanting to make a few improvements on it (like registering a single client-side function that accepts and processes minimum length as one of the arguments), but here's my mimimum length validator control's source:

using System.Web.UI;
using System.Web.UI.WebControls;
using System.ComponentModel;
using System.Text;

namespace ClubCrossControls
{
	/// <summary>
	/// Summary description for MinimumLengthValidator.
	/// </summary>
	[DefaultProperty("MinimumLength"),
	ToolboxData("<{0}:MinimumLengthValidator MinimumLength=0 ErrorMessage=\"Does Not Meet Minimum Length Requirement\" Text=* runat=server></{0}:MinimumLengthValidator>")]
	public class MinimumLengthValidator : CustomValidator
	{
		private int minLength;

		public MinimumLengthValidator()
		{}

		protected override void OnInit(System.EventArgs e)
		{
			base.OnInit (e);

			//register server-side script
			this.ServerValidate += 
				new ServerValidateEventHandler(this.TextValidate);
		}


		override protected void OnPreRender(System.EventArgs e)
		{
			base.OnPreRender (e);
			
			//register client-side validator
			if( this.EnableClientScript )
			{
				//if blank, use default
				if( this.ClientValidationFunction == "" )
					this.ClientValidationFunction = this.ID + "validateLength";
				//if default is not overridden
				if( this.ClientValidationFunction == this.ID + "validateLength" )
					Page.RegisterClientScriptBlock( this.ID +"MinScript", GetValidationScript() );
			}
		}

		private string GetValidationScript()
		{
			StringBuilder sb = new StringBuilder();

			sb.Append( "<SCRIPT LANGUAGE=\"JavaScript\">" );
			sb.Append(	"function " );
				sb.Append( this.ID );
					sb.Append( @"validateLength(oSrc, args){
									args.IsValid = (args.Value.length >=" );
										sb.Append( MinimumLength.ToString() );
					sb.Append( @");
					}
				</SCRIPT>" );

			return sb.ToString();
		}

		protected void TextValidate(object source, ServerValidateEventArgs args)
		{
			args.IsValid = (args.Value.Length >= MinimumLength);
		}

		/// <summary>
		/// The minimum length, in characters, for the control.
		/// </summary>
		[Category("Custom Properties"),
				Description("The minimum length of the field in characters")]
		public int MinimumLength
		{
			get
			{
				return minLength;
			}
			set
			{
				minLength = value;
			}
		}
	}
}

 

[crazyboybert]

Kalisto:

If you want to restrict characters then you can be more explicit in the expression as to what is allowed.

^[a-zA-Z0-9]{4,}$

for example will only allow lowercase and uppercase letters and numbers in the field. If you wanted to allow other characters you could add them in like...

^[a-zA-Z0-9_.]{4,}$

Alternatively you can use a hat at the start of the grouping to say "not" allowed like this....

^[^%]{4,}$

This would allow any characters other than % to pass through. Doing it this way it is much harder to be sure you have included every disallowed character so in most cases I wouldnt do this.

Here's a link to the MSDN documentation on regular expression if you want to find out more...

http://msdn.microsoft.com/library/d...l/cpconregularexpressionslanguageelements.asp

HTH

Rob

Go placidly amidst the noise and haste, and remember what peace there may be in silence - Erhmann 1927

 

[crazyboybert]

BB

I'll check out the validator later and let you know any feedback.

Rob

Go placidly amidst the noise and haste, and remember what peace there may be in silence - Erhmann 1927