implement hasFormChanged

[web-bert]

Is it possible cross-bowser to implement a function to tell you if the form has changed? Is this something we should have at all?

An example (which obviously doesn't account for all input types):

function hasFormChanged( form ){

        var elements = form.elements,
            element,
            i = 0,
            hasChanged = false;

        while( ( element = elements[ i++ ] ) ){

            switch( element.type ){
                case 'text':
                case 'textarea':
                    //console.log( 'text: ' + element.defaultValue + ' === ' + element.value, element.defaultValue === element.value );
                    hasChanged = ( element.defaultValue !== element.value );
                break;
                case 'select-one':
                    //console.log( 'select-one: ' + element.selectedIndex + ': ' + element.options[ element.selectedIndex ], element.options[ element.selectedIndex ].defaultSelected );
                    hasChanged = !element.options[ element.selectedIndex ].defaultSelected;
                break;
                case 'checkbox':
                    //console.log( 'checkbox: ' + element.checked +' === '+ element.defaultChecked, element.checked === element.defaultChecked );
                    hasChanged = ( element.checked !== element.defaultChecked );
                break;
            }

            if( hasChanged ){
                break;
            }
        }

        return hasChanged;
    }

[adamsilver]

Yes. Can detect existence of properties and then create that function. Can be made up of smaller functions for each e.g. hasTextBoxChanged, hasSelectChanged On Apr 7, 2014 9:20 AM, "web-bert" notifications@github.com wrote:

Is it possible cross-bowser to implement a function to tell you if the form has changed? Is this something we should have at all?

An example (which obviously doesn't account for all input types):

function hasFormChanged( form ){

    var elements = form.elements,
        element,
        i = 0,
        hasChanged = false;

    while( ( element = elements[ i++ ] ) ){

        switch( element.type ){
            case 'text':
            case 'textarea':
                //console.log( 'text: ' + element.defaultValue + ' === ' + element.value, element.defaultValue === element.value );
                hasChanged = ( element.defaultValue !== element.value );
            break;
            case 'select-one':
                //console.log( 'select-one: ' + element.selectedIndex + ': ' + element.options[ element.selectedIndex ], element.options[ element.selectedIndex ].defaultSelected );
                hasChanged = !element.options[ element.selectedIndex ].defaultSelected;
            break;
            case 'checkbox':
                //console.log( 'checkbox: ' + element.checked +' === '+ element.defaultChecked, element.checked === element.defaultChecked );
                hasChanged = ( element.checked !== element.defaultChecked );
            break;
        }

        if( hasChanged ){
            break;
        }
    }

    return hasChanged;
}

Reply to this email directly or view it on GitHubhttps://github.com/rassie/jessie/issues/252 .

[web-bert]

I was thinking it would be easier to account for all future types by detecting the properties. but I'm not sure if it would be robust enough?:

if( typeof element.defaultValue !== 'undefined' ){

    hasChanged = ( element.defaultValue !== element.value );

} else if( typeof element.options !== 'undefined' ){

    hasChanged = !element.options[ element.selectedIndex ].defaultSelected;

} else if( typeof element.checked !== 'undefined' ){

    hasChanged = ( element.checked !== element.defaultChecked );
}

[david-mark]

I'd break it up as some (e.g. text inputs) are trivial (requiring just one rendition), but others (e.g. SELECT elements) will need more thought. For example, a SELECT can have more than one option checked.

On Mon, Apr 7, 2014 at 4:32 AM, web-bert notifications@github.com wrote:

I was thinking it would be easier to account for all future types by detecting the properties. but I'm not sure if it would be robust enough?:

if( typeof element.defaultValue !== 'undefined' ){

hasChanged = ( element.defaultValue !== element.value );

} else if( typeof element.options !== 'undefined' ){

hasChanged = !element.options[ element.selectedIndex ].defaultSelected;

} else if( typeof element.checked !== 'undefined' ){

hasChanged = ( element.checked !== element.defaultChecked );}

Reply to this email directly or view it on GitHubhttps://github.com/rassie/jessie/issues/252#issuecomment-39706614 .