hi all
solved
if we set TextBox.Template=null then TextBox Content will be removed
but we can define other template and
set programically it to TextBox.Template
for example:
<controltemplate x:key="NewTemp" targettype="{x:Type TextBox}" xmlns:x="#unknown">
<grid>
<textbox grid.column="0" />
</grid>
</controltemplate>
and C# code:
this.TextBox1.Template = FindResource("NewTemp") as ControlTemplate;
thanks.