modifying control properties !!

when I create a simple form application project in vc++ express

I have these two files created by default,

form1.h & project_name.cpp

now suppose i add a text box in form1

I'm not able to change the properties like text of this textbox from anywhere else other then form1.h (say if i want to change properties from this file project_name.cpp)

its a very basic doubt but I've done evrything from making textbox public to anything wierd possible :(

tia
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