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Edit checks which return false result in an error message being displayed to the user. By default this is the error message configured in this field on the edit check:

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For more complex it edit checks it may be useful to display a more specific error message. This is possible using the customError customErrorMessage function.

Using customErrorMessage from an Edit Check

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Please watch this walkthrough to see customErrorMessage in action:

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Here is the example shown in the walkthrough:

var value = itemJson.item.value;

var ret = false;
if (value == 0) {
    // just display the default error message.
} else if (value == 1) {
    customErrorMessage("The value is 1, but needs to be at least 3!");
} else if (value == 2) {
    customErrorMessage("Still not quite large enough...");
} else if (value >= 3) {
    ret = true;
}
return ret;

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