|
//------------------------------------------------------------------------------
// <copyright file="RegularExpressionValidator.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
/*
*/
namespace System.Web.UI.WebControls {
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Text.RegularExpressions;
using System.Drawing.Design;
using System.Web;
using System.Web.Util;
/// <devdoc>
/// <para>Checks if the value of the associated input control matches the pattern
/// of a regular expression.</para>
/// </devdoc>
[
ToolboxData("<{0}:RegularExpressionValidator runat=\"server\" ErrorMessage=\"RegularExpressionValidator\"></{0}:RegularExpressionValidator>")
]
public class RegularExpressionValidator : BaseValidator {
/// <devdoc>
/// <para>Indicates the regular expression assigned to be the validation criteria.</para>
/// </devdoc>
[
WebCategory("Behavior"),
Themeable(false),
DefaultValue(""),
Editor("System.Web.UI.Design.WebControls.RegexTypeEditor, " + AssemblyRef.SystemDesign, typeof(UITypeEditor)),
WebSysDescription(SR.RegularExpressionValidator_ValidationExpression)
]
public string ValidationExpression {
get {
object o = ViewState["ValidationExpression"];
return((o == null) ? String.Empty : (string)o);
}
set {
try {
Regex.IsMatch(String.Empty, value);
}
catch (Exception e) {
throw new HttpException(
SR.GetString(SR.Validator_bad_regex, value), e);
}
ViewState["ValidationExpression"] = value;
}
}
// The timeout for regex
public int? MatchTimeout { get; set; }
/// <internalonly/>
/// <devdoc>
/// AddAttributesToRender method
/// </devdoc>
protected override void AddAttributesToRender(HtmlTextWriter writer) {
base.AddAttributesToRender(writer);
if (RenderUplevel) {
string id = ClientID;
HtmlTextWriter expandoAttributeWriter = (EnableLegacyRendering || IsUnobtrusive) ? writer : null;
AddExpandoAttribute(expandoAttributeWriter, id, "evaluationfunction", "RegularExpressionValidatorEvaluateIsValid", false);
if (ValidationExpression.Length > 0) {
AddExpandoAttribute(expandoAttributeWriter, id, "validationexpression", ValidationExpression);
}
}
}
/// <internalonly/>
/// <devdoc>
/// EvaluateIsValid method
/// </devdoc>
protected override bool EvaluateIsValid() {
// Always succeeds if input is empty or value was not found
string controlValue = GetControlValidationValue(ControlToValidate);
Debug.Assert(controlValue != null, "Should have already been checked");
if (controlValue == null || controlValue.Trim().Length == 0) {
return true;
}
try {
// we are looking for an exact match, not just a search hit
// Adding timeout for Regex in case of malicious string causing DoS
Match m = RegexUtil.Match(controlValue, ValidationExpression, RegexOptions.None, MatchTimeout);
return(m.Success && m.Index == 0 && m.Length == controlValue.Length);
}
catch (ArgumentOutOfRangeException) {
throw;
}
catch {
Debug.Fail("Regex error should have been caught in property setter.");
return true;
}
}
}
}
|