2022-02-11
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#flutter
Eshiet Ekemini
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Feb 11, 2022 â‹… 10 min read

Flutter form validation: The complete guide

Eshiet Ekemini A graduate of University of Uyo and a tech enthusiast, Ekemini has been building for mobile for two years, with a particular focus on Kotlin and Flutter.

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4 Replies to "Flutter form validation: The complete guide"

  1. I got an error in the validation section then I solved the problem as follows;

    validator: (val) {
    if (!val.isValidName)
    return ‘Enter valid email’;
    },

    You cant return string or null in function, so you need to return empty string.If you do that it will solve.I did share code in the below

    validator: (val) {
    if (!val.isValidName)
    return ‘Enter valid email’;
    return ”;
    },

  2. Wow! So helpful in getting a handle on various validation and input field formatting in Flutter. Thank you! This is helpful and useful because it shows actual working examples, building from the basic form. The registration form is a particularly good example because it illustrates most use cases for starting programmers (in general, or just new to Flutter, like me).
    I’m not quite finished as I’ve got what I need for my current project, nonetheless I’m looking forward to the remainder (Making a custom form field, on). It really appears to fulfill on it’s title!

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