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Unplanned
Last Updated: 22 May 2025 12:12 by Patrice Boissonneault
Derek
Created on: 22 May 2025 06:41
Category: Input
Type: Bug Report
0
Uncaught TypeError: Cannot read properties of null (reading 'className')

The issue occurs when setting the Enabled property to false, which triggers a JavaScript error and causes the components to break.

Code to replicate the problem

<telerik:RadTextBox ID="RadTextBox1" runat="server" Enabled="false"></telerik:RadTextBox>
2 comments
Patrice Boissonneault
Posted on: 22 May 2025 12:12
Will this fix be in next release? If so, we will wait here. We do not like workarounds. Thanks for confirming.
ADMIN
Attila Antal
Posted on: 22 May 2025 09:17

Hello Derek,

Thank you for reporting the problem! We have identified the issue in the source code and found a temporary workaround that can be used until this is fixed.

Workaround

As a workaround, you can add the following script override to the page.

Note: It is important to add the Script right after the ScriptManager/RadScriptManager declaration and not before.

<script>
    (function () {
        try {
            var original_set_enabled = Telerik.Web.UI.RadInputControl.prototype.set_enabled;
            Telerik.Web.UI.RadInputControl.prototype.set_enabled = function (value) {

                if (this._enabled !== value) {
                    this._enabled = value;

                    if (this._textBoxElement) {
                        this._textBoxElement.disabled = !this._enabled;
                    }

                    if (this.get_wrapperElement())
                        this.updateCssClass();

                    this.updateClientState();

                    if (this.get_enableAriaSupport()) {
                        this._applyAriaStateChange('disabled', !value);
                    }

                    this.raisePropertyChanged('enabled');
                }
            }
        } catch (e) {
            // There is nothing to do.
        }
    })();
</script>

 

 

Regards,
Attila Antal
Progress Telerik

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