该段代码中的value是谁的属性
do case case this.value=1
thisform.backcolor=rgb(225,0,0)
case this.value=2
thisform.backcolor=rgb(0,255,0)
case this.value=3
thisform.backcolor=rgb(0,0,255)
case this.value=4
thisform.backcolor=rgb(0,0,0)
case this.value=5
thisform.backcolor=rgb(225,255,255)
endcase
thisform.refresh
该段代码中的value是谁的属性,谁来解释一下