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Error KeyNotFoundException About Key inputElementValue


Product UI for Blazor


When I use Add, Delete or Edit Commands in the Grid, I get an error KeyNotFoundException about a key inputElementValue not present in the dictionary.

A date field in the Grid popup editing is crashing.

When I set the focus on a DatePicker or DateInput and tab to switch to another component, I get an error.

Error Message

System.Collections.Generic.KeyNotFoundException: The given key 'inputElementValue' was not present in the dictionary.

Possible Cause

This error indicates that the app is using an old or wrong version of the telerik-blazor.js file, for example, after a component version upgrade.


To resolve the error:

  • (if using CDN) Update the telerik-blazor.js file URL to the correct version.
  • (if using static assets) Clear the browser cache.
  • (if using a local JS file) Replace the telerik-blazor.js file with the new version.

See Also

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