Java 如何只测试字符串中的字母或撇号?
我需要检查字符串中的一些内容:Java 如何只测试字符串中的字母或撇号?,java,vb.net,string,Java,Vb.net,String,我需要检查字符串中的一些内容: 第一个字母必须是大写字母 只有字母或撇号(') 最多可以使用2个撇号 下面的代码总是返回字符串不一致,除非我只输入1个大写字母。我如何纠正它以满足我的要求 Private Function setName(ByVal pName As String) Dim letters As Integer() Dim aphCount As Integer = 0 Dim isvalid As Boolean = True For i As
Private Function setName(ByVal pName As String)
Dim letters As Integer()
Dim aphCount As Integer = 0
Dim isvalid As Boolean = True
For i As Integer = 0 To pName.Length - 1 Step 1
ReDim letters(i)
letters(i) = Asc(pName.Substring(i, 1))
Next
If Not letters(0) >= 65 And letters(0) <= 90 Then
isvalid = False
End If
For i As Integer = 1 To pName.Length - 1 Step 1
If letters(i) >= 39 And letters(i) <= 122 Then
If letters(i) = 39 Then
aphCount += 1
If aphCount > 2 Then
isvalid = False
End If
ElseIf letters(i) >= 65 And letters(i) <= 90 Then
ElseIf letters(i) >= 97 And letters(i) <= 122 Then
Else isvalid = False
End If
Else isvalid = False
End If
Next
If isvalid = False Then
If MsgBox("you put in an invalid name", MsgBoxStyle.RetryCancel, "name error") = MsgBoxResult.Cancel Then
pName = "Hero" & heroCount
Else
pName = inputName()
pName = setName(pName)
End If
End If
Return pName
End Function
您的代码对于您尝试执行的操作非常复杂。它很长,里面有很多。您可以使用正则表达式或通过正则比较字符串中的每个元素来解决此问题。这是第二种方法的一个示例:
Private Function IsValidName(name As String) As Boolean
If String.IsNullOrWhiteSpace(name) Then Return False
Return Char.IsUpper(name.AsEnumerable().First()) AndAlso
name.AsEnumerable().All(Function(c) Char.IsLetter(c) OrElse c.Equals("'"c)) AndAlso
name.AsEnumerable().Count(Function(c) c.Equals("'"c)) <= 2
End Function
私有函数IsValidName(名称为字符串)为布尔值
如果String.IsNullOrWhiteSpace(name),则返回False
返回Char.IsUpper(name.AsEnumerable().First())和
name.AsEnumerable().All(函数(c)Char.isleter(c)或lse c.Equals(“'c)),以及
name.AsEnumerable().Count(函数(c)c.Equals(“'c))您可以用两行正则表达式来实现这一点
Private Function IsValidName(name As String) As Boolean
Dim match = Regex.Match(name, "^[A-Z]((')|[A-Za-z])*$")
Return match.Success AndAlso match.Groups(2).Captures.Count <= 2
End Function
私有函数IsValidName(名称为字符串)为布尔值
Dim match=Regex.match(名称,“^[A-Z](“)|[A-Za-Z])*$”)
请返回match.Success和also match.Groups(2).Captures.Count,重新格式化代码以提高可读性-很难读取签名和函数体。
Private Function IsValidName(name As String) As Boolean
Dim match = Regex.Match(name, "^[A-Z]((')|[A-Za-z])*$")
Return match.Success AndAlso match.Groups(2).Captures.Count <= 2
End Function