Is Dependency Validation possible in KnockOut.js

Question

Usually validations work independent with respective binded content, eg http://jsfiddle.net/supercool/JL26Z/53/

But I have two text boxes name1 & name2, as mentioned in fiddle, I need to do show validation is failed if following condition fails:

name1 is mandatory if name2 is not entered.
name2 is mandatory if name1 is not entered.
if name1 & name2 left empty i need to show error message i.e validations failed.

If I got you confused: in short I am looking for validations to pass if text is entered in any of the textboxes.

https://github.com/Knockout-Contrib/Knockout-Validation/wiki/Conditional-Validation — , Aug 11 '14 at 09:56
http://stackoverflow.com/questions/14331948/knockout-validation-of-two-interdependent-fields — , Aug 11 '14 at 09:57

score 1 · Accepted Answer · edited May 23 '17 at 10:33

1

Do it like @delixfe suggested in another question here on SO:

var Phone = function () {
    var self = this;

    self.name1 = ko.observable("");
    self.name2 = ko.observable("");

    self.numbersHaveNoValue = ko.computed(function () {
        var value1 = self.name1(), value2 = self.name2();
        return !ko.validation.rules.required.validator(value1, true) &&
               !ko.validation.rules.required.validator(value2, true);
    });

    self.Validation = ko.validatedObservable([
        self.name1.extend({ required: { onlyIf: self.numbersHaveNoValue }}),
        self.name2.extend({ required: { onlyIf: self.numbersHaveNoValue }})
    ]);
}

see fiddle

edited May 23 '17 at 10:33

Community

1
1

answered Aug 11 '14 at 10:04

Andreas i will look into it and let you know . – super cool Aug 11 '14 at 10:09
when i enter something in textbox2 and press submit leaving textbox1 empty its shooting me error which should not happen . any ideas ? – super cool Aug 11 '14 at 10:11
gotcha bro .! used additional `ko.computed` . cheers – super cool Aug 11 '14 at 10:19
nah, this was a mistake in the first version, where I did `...required.validator(valu1, true)` for both name1 and name2 – Aug 11 '14 at 10:28
ha yes thats right . i changed to value1 to value 2 rather keeping both same its doesn't work earlier but now its working like charm intrestingly . – super cool Aug 11 '14 at 11:10

Is Dependency Validation possible in KnockOut.js

1 Answers1