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blockly > FieldValidator
FieldValidator type
A function that is called to validate changes to the field's value before they are set.
Signature:
export type FieldValidator<T = any> = (newValue: T) => T | null | undefined;
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Last updated 2024-09-18 UTC.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2024-09-18 UTC."],[[["`FieldValidator` is a function used to validate changes to a field's value before they are applied."],["It takes the new value as input and should return the validated value, `null`, or `undefined`."],["Returning `null` or `undefined` signifies an invalid value and prevents the change."],["The validated value, if returned, will be the value ultimately set for the field."]]],[]]