敲除数据绑定（如果存在其他条件）

Question

In my current project, I have a knockout binding where the layout height should be applied according to the value received as true or false. Following is my binding code

data-bind="style: {height: showOld ? '392px' : '275px'}"

The showOld gives either true or false correctly, but, regardless what it returns, it always take 392px . If the showOld gives true then 392px should return else 275px should return. Any help to fix this issue is highly appreciate.

Thanks

Answer 1

If your showOld is ko.observable then you need to write showOld() (because ko.observable is a function) to get its value in your expression:

data-bind="style: {height: showOld() ? '392px' : '275px'}"

From the documentation :

To read the observable's current value, just call the observable with no parameters.

To write a new value to the observable, call the observable and pass the new value as a parameter. For example, calling myViewModel.personName('Mary') will change the name value to 'Mary'.