Question

当我将两个字符串更改为double时，然后减去它们，答案始终为0.有没有人知道解决此问题的方法？

    Dim TotalCashNum As Double
    Dim InsertCoinNum As Double
    Dim NewTotalCash As Double

    InsertCoinsTextBox.Text = Convert.ToDouble(InsertCoinNum)
    TotalCash.Text = Convert.ToDouble(TotalCashNum)
    NewTotalCash = TotalCashNum - InsertCoinNum
    MsgBox(NewTotalCash)

提前致谢

Answer 1

这些行错了：

InsertCoinsTextBox.Text = Convert.ToDouble(InsertCoinNum)
TotalCash.Text = Convert.ToDouble(TotalCashNum)

应该是

InsertCoinNum = CDbl(InsertCoinsTextBox.Text )
TotalCashNum = CDbl(TotalCash.Text)

Answer 2

您正在将文本框的值分配给错误的变量。

应该是：

Dim TotalCashNum As Double
Dim InsertCoinNum As Double
Dim NewTotalCash As Double

InsertCoinNum = CDbl(InsertCoinsTextBox.Text )
TotalCashNum = CDbl(TotalCash.Text)
NewTotalCash = TotalCashNum - InsertCoinNum

VB - 计算总是返回0

2 个答案: