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Solution
Submitted about 2 years ago

Age Calculator App using BEM methodology

bem
Deivisson Lisboa•190
@DeivissonLisboa
A solution to the Age calculator app challenge
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Solution retrospective


I had some difficulties implementing error handling for incorrect input. If anyone has any suggestions or tips for improving my error handling, I would greatly appreciate it.

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Community feedback

  • Erine Natnat•160
    @rinster
    Posted about 2 years ago

    Amazing job on the animation and in vanilla JS too! I did mines in Vue.js and used Moment.JS library to handle the date logic.

    For handling errors, I recommend having a global object to hold your error states and update it accordingly:

    const errors = {
    	'errorsPresent' : 'false',
    	'dayError': "",
    	'monthError': "",
    	'yearError': ""
    }
    

    I use an errorsPresent key so I don't have to check the entire object. A sample validation logic can look like this:

    
    // Year
    let currentYear =  new  Date().getFullYear();
    if (yearInput === "") {
    	errors.yearError = "This field is required";
    	errors.errorsPresent = true;
    } else if (isNaN(Number(yearInput))) {
    	errors.yearError = "Must be a valid year";
    	errors.errorsPresent = true;
    } else if (Number(yearInput) > currentYear) {
    	errors.yearError = "Must be in the past";
    	errors.errorsPresent = true;
    }
    

    So if errors.errorsPresent === true you can update the DOM by inserting css style classes and the error messages from your errors object.

    .is-danger--border {
    	border: 1px solid hsl(0, 100%, 67%);
    }
    
    .is-danger--text {
    	color: hsl(0, 100%, 67%);
    }
    

    Don't forget to clear your error states and messages if the user updates the date again. Hope this helps :)

    Marked as helpful

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