docs(kb): Document inputelementvalue JS error (#1401)

Author: dimodi

knowledge-base/keynotfoundexception-inputelementvalue.md

@@ -0,0 +1,56 @@
+---
+title: Error KeyNotFoundException About Key inputElementValue
+description: How to troubleshoot and fix exception error Error KeyNotFoundException The given key inputElementValue was not present in the dictionary
+type: troubleshooting
+page_title: Error KeyNotFoundException - the given key inputElementValue was not present in the dictionary
+slug: common-kb-keynotfoundexception-inputelementvalue
+position:
+tags: telerik, blazor, exception, error
+ticketid: 1604193, 1602978, 1601905, 1601905
+res_type: kb
+---
+
+## Environment
+
+<table>
+    <tbody>
+        <tr>
+            <td>Product</td>
+            <td>Telerik UI for Blazor</td>
+        </tr>
+    </tbody>
+</table>
+
+
+## Description
+
+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
+
+>warning System.Collections.Generic.KeyNotFoundException: The given key 'inputElementValue' was not present in the dictionary.
+
+
+## Cause\Possible Cause(s)
+
+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]({%slug upgrade-tutorial%}).
+
+
+## Solution
+
+To resolve the error:
+
+* (if using [CDN]({%slug getting-started/what-you-need%}#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
+
+* [Telerik UI for Blazor version upgrade steps]({%slug upgrade-tutorial%})
+* [JavaScript error troubleshooting]({%slug troubleshooting-js-errors%})

troubleshooting/js-errors.md

@@ -104,6 +104,12 @@ Another possible cause is a *race condition* during fast multiple recreations of
 * Do not call `StateHasChanged()` inside `EventCallback` methods (e.g. Button click handlers). Blazor executes `StateHasChanged()` automatically in such cases.
 * Throttle the user behavior, so that rapid subsequent navigation is not possible.
 
+## KeyNotFoundException: The given key inputElementValue was not present
+
+The full exception message is `System.Collections.Generic.KeyNotFoundException: The given key 'inputElementValue' was not present in the dictionary.`
+
+This error indicates that [the app is using an old or wrong version of the `telerik-blazor.js` file]({%slug common-kb-keynotfoundexception-inputelementvalue%}), for example, after a component version upgrade.
+
 ## Object doesn't support property or method 'assign'
 
 Under IE, you may get errors similar to `Object doesn't support property or method 'assign'` or errors that relate other modern JS features that are not supported under IE. The reason is that we use modern code that may not work under IE - it is not one of the [browsers we support]({%slug system-requirements%}#browser-support), and WebAssembly does not work on it anyway, so modern Blazor apps won't run on IE regardless.