string-conversion - 将 String 转换为请求的 Nullable 数据类型

Question

需要将基于字符串的值转换为返回为Nullable 数据类型的任何请求格式，包括但不限于 WCF QueryString 解析器。

标签： string-conversion

Answer 1

请找到以下代码，该代码采用字符串值并将转换后的值作为Nullable 请求的数据类型返回

Public Function GetStringValueOrNull(Of T As Structure)(ByVal sInputString As String) As Object
    Try
        'Validate sInputString and proceed
        If sInputString IsNot Nothing Then
            'Input String found, validate length to better ensure validity
            If sInputString.Length > 0 Then
                'Valid input found, proceed
                Dim Result As Object
                'Convert string to requested format
                Result = CType(Convert.ChangeType(sInputString, GetType(T)), T)
                'Return Value
                Return Result
            Else
                'String length is 0, return Nothing
                Return Nothing
            End If
        Else
            'No string input found, return Nothing
            Return Nothing
        End If
    Catch ex As Exception
        'Error occurred, return Nothing
        Return Nothing
    End Try
End Function