ExportConversions doesn't work in all cases

[pappfer]

Prerequisites

• I have searched for similar issues in both open and closed tickets and cannot find a duplicate.
• The issue still exists against the latest master branch of yii2-grid.
• This is not an usage question. I confirm having gone through and read the documentation and demos.
• This is not a general programming / coding question. (Those should be directed to the webtips Q & A forum).
• I have attempted to find the simplest possible steps to reproduce the issue.

I'm using the latest version of yii2-grid and exportConversions option doesn't work for me for checkbox, it works when using simple tags, though.

Example

This works:

[
    'from' => '<i class="fa fa-check-square-o text-success" aria-hidden="true"></i>',
    'to' => Yii::t('app', 'Yes'),
],

This doesn't:

[
    'from' => '<div class="checkbox checkbox-primary"><input checked="checked" disabled="disabled" type="checkbox"><label></label></div>',
    'to' => Yii::t('app', 'Yes'),
],

I'd like the '<div class="checkbox checkbox-primary"><input checked="checked" disabled="disabled" type="checkbox"><label></label></div>' markup to be converted. Is it possible?

It would also be nice to add a feature to use different conversions for different export types. For example PDF supports if there's a check icon ( ✓ ) in the 'to' field, while Excel doesn't.

[kartik-v]

Related to enh #843 and #844.