vb常数自定义如何设置

Const HandleTime = 2 是正常的
我想让这个2变成可调整的弄了个文本框
Const HandleTime = 环境变量.Text8
编译的时候提示要求常数表达式该怎么办

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Function m() k = Text1.Text Dim p(4 To 7) As Double p(4) = 0.95 p(5) = 0.9 p(6) = 0.8 p(7) = 0.75 m = p(k) End Function

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