Here's what I am trying to do. I press a button on the form and it is suppose to concatenate the button's text to another variable. But it isn't doing it at all. Here's part of the code I am using...

Code:
.DATA?
buff db 80 dup(?)
.
.
.
.CODE
.
.
.
.IF ax==BTN_ID1
     shr eax, 16
          .IF ax==BN_CLICKED
               INVOKE lstrcat, buff, ADDR b1Txt
               INVOKE SetWindowText, hEdit, ADDR buff
          .ENDIF
.ENDIF

;NOTE:  hEdit is the handle of my edit control and b1Txt is the text I want to add to buff.
I am assuming that either "buff" is declared incorrectly, or I am screwing something up with the "lstrcat" call. If you would like to see the entire code, tell me.