Fixed a bug in date/time conversion when special input is used.

[yui10]

Added error handling for special input in date/time conversion.

Pull request type

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• Bugfix
• New feature or enhancement
• UI change (please include screenshot!)
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What is the current behavior?

Issue Number: DevToys-app/DevToys#1349

What is the new behavior?

• Added error handling to DateHelper.cs. If an error occurs, return the original value.
• Change Convert.ToInt32 to int.TryParse and process the error.

Other information

Translated by DeepL

Quality check

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• Did you follow the code style guideline as described in CONTRIBUTING.md
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[veler]

Hi,
This is awesome, thank you !