Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Configuration/System/Configuration/StringValidator.cs

@@ -0,0 +1,71 @@
+//------------------------------------------------------------------------------
+// <copyright file="StringValidator.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//------------------------------------------------------------------------------
+
+using System;
+using System.Collections;
+using System.IO;
+using System.Reflection;
+using System.Security.Permissions;
+using System.Xml;
+using System.Collections.Specialized;
+using System.Globalization;
+using System.ComponentModel;
+using System.Security;
+using System.Text;
+using System.Text.RegularExpressions;
+
+namespace System.Configuration {
+
+    public class StringValidator : ConfigurationValidatorBase {
+        private int _minLength;
+        private int _maxLength;
+        private string _invalidChars;
+
+        public StringValidator(int minLength)
+            : this(minLength, int.MaxValue, null) {
+        }
+        
+        public StringValidator(int minLength, int maxLength)
+            : this(minLength, maxLength, null) {
+        }
+        
+        public StringValidator(int minLength, int maxLength, string invalidCharacters) {
+            _minLength = minLength;
+            _maxLength = maxLength;
+            _invalidChars = invalidCharacters;
+        }
+
+        public override bool CanValidate(Type type) {
+            return (type == typeof(string));
+        }
+        
+        public override void Validate(object value) {
+            ValidatorUtils.HelperParamValidation(value, typeof(string));
+
+            string data = value as string;
+            int len = (data == null ? 0 : data.Length);
+
+            if (len < _minLength) {
+                throw new ArgumentException(SR.GetString(SR.Validator_string_min_length, _minLength));
+            }
+
+            if (len > _maxLength) {
+                throw new ArgumentException(SR.GetString(SR.Validator_string_max_length, _maxLength));
+            }
+
+            // Check if the string contains any invalid characters
+            if ((len > 0) && (_invalidChars != null) && (_invalidChars.Length > 0)) {
+                char[] array = new char[_invalidChars.Length];
+
+                _invalidChars.CopyTo(0, array, 0, _invalidChars.Length);
+
+                if (data.IndexOfAny(array) != -1) {
+                    throw new ArgumentException(SR.GetString(SR.Validator_string_invalid_chars, _invalidChars));
+                }
+            }
+        }
+    }
+}