TextField autoconvert string to number

I have a problem with the control TextField. The control is located in the grid. The control is set:
InputType = InputType.Text,
AutoRender = False.
When working with numbers I have a few problems:
- After saving the '24,3 ', the comma is converted to dot
- After entering the value '24,0 ', 0 is removed when reading data
- When I try to read a stored value '24,5. ' on page generates an error:
Ext.ComponentManager.onAvailable("MyPanel",functio n(){Ext.net.append(Ext.getBody(),["",""].join(''));Ext.net.addTo(

In my project in this TextField, each value should be processed as text (it should not be rounded numerically).