Question

例如，150safdsdfsdf123456应该产生150

如果文字是150，那就很简单了。只需使用val。但是，我希望能够阅读150sdfsdfsdafsadfwhatever。

我该怎么做？

Answer 1

使用正则表达式（正则表达式）从字符串中提取数字

Dim value1 as String
Dim temp As Regex = New Regex("\d+")
Dim match As Match = temp.Match("23333 dsadsa fd")
If match.Success Then
    value1 = match.Value
    Console.WriteLine(value1)
End If

Answer 2

Dim input As String = "150safdsdfsdf" ' input string contains alphanumeric characters.
Dim output As String = New String((From c As Char In input Select c Where Char.IsDigit(c)).ToArray())
' output is a string variable, in the RHS select each character from the input string ('c') 
'and check whether it is a digit or not using IsDigit Function. 
' if yes it is append with the output string 
' else it is neglected.
'hence we will get only numbers as oru output 
msgbox (output)' output will be 150

Answer 3

如果您只想要开头的数字而中间或结尾没有任何内容，请使用此

Dim input As String = "150safdsdfsdf150"
Dim output As String = New String(input.TakeWhile(Function(c) IsDigit(c)).ToArray())

Val()实际上有什么问题？

Dim s = "150.9sdfsdfsdafsadfwhatever654"
Dim d = Val(s)

d将是150.9（它接受小数！）

Answer 4

要匹配字符串开头的数字，可以使用正则表达式：

Imports System.Text.RegularExpressions

Dim input As String = "150safdsdfsdf123456"
Dim re As New Regex("^\d+")
Dim output As String = re.Match(input).Value

注意^符号，表示字符串的开头。因此，例如，a150safdsdfsdf123456将无法匹配。

如何从字符串前面的数字中获取价值？

4 个答案: