将文本框字符串转换为双 VB.NET
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Convert Textbox string to Double VB.NET
提问by GAltelino
i'm getting a problem everytime I try to convert an textbox value to a double, the value in the textbox will be used in a calculation with another double, and it's entried from keyboard, everytime i tried to run it I used just numbers on the textbox.
每次我尝试将文本框值转换为双精度值时都会遇到问题，文本框中的值将用于与另一个双精度值的计算，并且它是从键盘输入的，每次我尝试运行它时我只使用数字文本框。
dim temporaryProduct as string
Dim value, convertValue, finalValue As Double
temporaryProduct = mathForm.valueBox.tostring ' I've tried with .text too
If Double.TryParse(temporaryProduct, value) Then 'Convert to double
convertValue = value
Else
MsgBox("Tryparse error")
Exit Sub
End If
Everytime i try to convert the textbox string i get "Tryparse error", i really don't know what i'm doing wrong, and i need it to be in double.
每次我尝试转换文本框字符串时，我都会收到“Tryparse 错误”，我真的不知道自己做错了什么，我需要将它变成双份。
采纳答案by LarsTech
Try using just the Text property:
尝试仅使用 Text 属性：
temporaryProduct = mathForm.valueBox.Text
If you use the ToString function on a TextBox, you get something like this:
如果在 TextBox 上使用 ToString 函数，则会得到如下结果：
System.Windows.Forms.TextBox, Text: ???
System.Windows.Forms.TextBox，文本：？？？
which is obviously not a value you can use.
这显然不是您可以使用的值。
