Last Updated: 20 Feb 2017 07:16 by Scott Waye
You have the following scenario:

The UpdateValueEvent property is set to "LostFocus". You have bound the Value property of the control to a property from your ViewModel. 

When this property is changed programmatically from negative to positive several times, the Value property of the control isn't updated correctly.

It stays negative when it must stay positive.

Workaround (if applicable):
You can change the UpdateValueEvent property to "PropertyChanged" 

Other Possible workaround (if the bound property is named "Sum")

private void radMaskedNumericInputSum_ValueChanging_1(object sender, Telerik.Windows.Controls.MaskedInput.RadMaskedInputValueChangingEventArgs e)
    if (this.Sum != (double)e.NewValue)
        e.Handled = true;
Last Updated: 27 Dec 2016 14:12 by Dinko
In order to reproduce,  you need to focus the control when you run the application.

1.When you press the backspace key it removes the last character and after pressing it a second time the character will be replaced with the removed character.

2. When paste(Ctrl+V) a text in the control, the text is ignoring the current position of the caret and position at the beginning of the control.
Last Updated: 01 Apr 2016 14:08 by ADMIN
Mask="" (no-mask) and FormatStyring =n3 or n4 , n5.

Value is 0.

Typing 0 then ".", then 0, then 0, then 5 produces 0.5000 but it should produce 0.0050.

Fix available in LIB Version 2016.1.404.
Last Updated: 04 Oct 2016 14:16 by ADMIN
Last Updated: 22 Dec 2015 11:48 by ADMIN
RadGridView with CellEditTemplate with RadMaskedDateTimeInput.

Select a GridViewRow. Press ALT  + N Key (or other key with letter/digit).

Argument Exception occurs in MaskedDateTimeGridViewEditor.

The issue is reproducible in Q3 2015 SP (1104) version of Telerik UI for WPF.
The fix will be available in Q1 2016 Release.
Last Updated: 22 Jan 2016 14:55 by ADMIN
Mask="Pddd" should disallow letters.

However, after select all, you can type letter in the position of the first "d"

Available in LIB Version: 2016.1.125.
Last Updated: 24 Oct 2016 14:39 by Greg
Bug details:
OS: Windows 10.
VS: 2015 professional
Telerik version: 2015.2 SP1

Code sample:
<Window x:Class="RadMaskedInputBug.MainWindow"
        <telerik:RadTextTimeInput />

The designer crashes and shows only the exception:
InvalidOperationException: Can only base on a Style with target type that is base type 'RadMaskedTextInput'.

Telerik has submitted a bug report to Microsoft. You can check its progress here: 
On 21/12/2015 Microsoft commented that a fix has been submitted and will be available in the next update.
Last Updated: 09 Oct 2017 12:09 by ADMIN
Fix available in LIB Version 2017.3.1009.
Last Updated: 28 Dec 2016 13:57 by ADMIN
The Mask property of the RadMaskedDateTimeInput cannot be set or changed via binding. Internally it is always set to "d".
Last Updated: 14 Feb 2018 13:50 by ADMIN
Created by: Pavel R. Pavlov
Comments: 0
Category: MaskedInput
Type: Bug Report
If there is a whitespace in the Mask of the control and you try to paste a value containing whitespace, the control will trim the user input.


Mask="(###) ###-####

User Input: 1234567890

The MaskedText should be: (123) 456-7890

If you copy this input and try to paste it into a control with the same Mask you will get (123) 45-6789 which is not correct.

Possible workarounds !!!

1. In a scenario when the user will enter only digits in the MaskedTextInput for a phone number is to restrict the input by setting the following mask.

<telerik:RadMaskedTextInput EmptyContent="Enter digits" Mask="(d3) d3-d4" />

2. The second workaround is to use non breaking space in Mask, this way there won't be a match between space by the user and space in the mask symbols.
Last Updated: 05 Jan 2015 13:44 by ADMIN
Pasting text in TextInput with No-Mans and UpdateValueEvent=LostFocus is not successful.

This operation clears the whole Value.

 <telerik:RadMaskedTextInput Mask="" UpdateValueEvent="LostFocus"/>

Available in LIB version: 2014.3.1305
Last Updated: 04 Feb 2016 13:22 by ADMIN
The 'hh:mm' Mask is not applied correctly in the DateTimeInput when the control is focused.

For example if the date is 2014-05-23, 22:30, and the Mask property of the control is set to 'hh:mm' the displayed text should be 10:30. Currently, this text is displayed only if the input is not focused, otherwise the text changes to 22:30
Last Updated: 27 Dec 2016 13:44 by ADMIN
Mask is "a-a". Value is set to "M-M".

The MaskedTextInput control must internally coerce the Value to "MM".
Instead , MaskedTextInput'Value is "M-" which is wrong.

Other example of the same issue:
Bound Value is bbaabbaabbdd, Mask is "aa-aa-aa-aa-aa-aa"
The result is - value becomes bbbbbbddaaaa.

Use custom Mask Token (check help article:

 public class CustomToken : ITokenValidationRule
        public bool IsRequired
            get { return false; }

        public bool IsValid(char ch)
            return ValidChars.Contains(ch.ToString());

        public char Token
            get { return '$'; }

        public TokenTypes Type
            get { return TokenTypes.AlphaNumeric; }

        private string myValidChars = "0123456789qwertyuioplkjhgfdsazxcvbnm";
        public string ValidChars
            get { return myValidChars; }

    TokenLocator.AddCustomValidationRule(new CustomToken());

   <telerik:RadMaskedTextInput Mask="$-$"  
Last Updated: 04 Jan 2016 15:58 by ADMIN
Numeric or Currency Input with Value = Null.

Clicking minus key (OemMinus or NumpadSubtract) places minus but Shift + OemPlus (or Numpad Add) does NOT remove the minus sign.

Will be available in Q1 2016 Release.
Last Updated: 05 Nov 2014 09:38 by ADMIN
Part of the Value or the whole value is selected in no-masked NumericInput.

Pasting a copied text is not successful. For example 4 is the value and 4 is selected. Pasting "123" produces "1" but it should produce "123".
Last Updated: 28 Aug 2014 13:27 by ADMIN
Created by: Petar Mladenov
Comments: 0
Category: MaskedInput
Type: Bug Report
MaskedNumericInput with Mask = #6.3. When there is no digit grouping (you can turn it off from  the region / format settings in windows, no digit grouping means no symbol for grouping) the control produces Exception on load.
Last Updated: 18 Nov 2014 14:42 by ADMIN
If you try to paste text in the RadMaskedTextInput control using the default ContextMenu, after the Clear button is pressed (or after delete with backspace), the Paste command is not working as expected.

Available in LIB version: 2014.3.1124
Last Updated: 21 Jul 2014 12:07 by ADMIN
Created by: Petar Mladenov
Comments: 3
Category: MaskedInput
Type: Bug Report
RadMaskedTextInput with no-mask => Mask="".

Selecting part of the value then paste works incorrectly. The selected text is not replaced and it is preserved, the copied text is inserted.

It is expected that the selected text is entirely replaced with the copied text.
Last Updated: 31 Jul 2014 14:30 by ADMIN
GridView with GridViewDataColumn.CellEditTemplate.

In it MaskedTextInput is initially Collapsed. Double clicking the Cell will produce a Null refecence exception.
Last Updated: 08 Dec 2016 09:41 by ADMIN
In MaskedTextInput the ClearButton will make the Value "" but it should make it NULL. All other InputControls have null value after pressing ClearButton.

No-masked TextInput works fine - the ClearButton makes the Value Null.

As a workaround, you can use the ClearCommand, bind it to Command from your ViewModel and the execute handler can set the bound Value to null.