C# VB.NET随机字符串函数的帮助？

我用C编写了一个函数来创建一个随机字符串，但我想将其转换为VB.NET，不幸的是，我对Visual Basic的了解远远少于对C的了解

下面是我的VB.NET函数：

' Function will take in the number of characters in the string, as well as the optional parameter of chars to use in the random string
    Private Function RandomString(ByVal Chars_In_String As Integer, Optional ByVal Valid_Chars As String = "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM")
        ' Create a string to hold the resulting random string
        Dim ReturnMe As String = ""

        ' Loop variable
        Dim i As Integer = 0

        ' Run while loop while i is less than the desired number of Chars_In_String
        While i < Chars_In_String
            ' Each time through, add to ReturnMe (selecting a random character out of the string of all valid characters)
            ReturnMe += Valid_Chars(random.[Next](0, Valid_Chars.Length))
        End While

        ' Return the value of ReturnMe
        Return ReturnMe
    End Function
    ' Create a new instance of the Random class, using a time-dependant default seed value
    Dim random As New Random()

    private static string RandomString(int Chars_In_String)
    {
        // Create a string to contain all valid characters (in this case, just letters)
        string all = "qwertyuiopasdfghjklzxcvbnmQWERTYIOPASDFGHJKLZXCVBNM";

        // Create a variable that will be returned, it will hold the random string
        string ReturnMe = "";

        // Run for loop until we have reached the desired number of Chars_In_String
        for (int i = 0; i < Chars_In_String; i++)
        {
            // Each time through, add to ReturnMe (selecting a random character out of the string of all valid characters)
            ReturnMe += all[random.Next(0, all.Length)];
        } 

        // Return the value of ReturnMe
        return ReturnMe;
    }
    // Create a new instance of the Random class, using a time-dependant default seed value
    static Random random = new Random();

正如您将看到的，它与我的C版本没有太大的不同，只是因为VB可以接受一个可选参数，所以我允许用户选择要在字符串中使用的字符，或者只使用默认字符

下面是我函数的C版本：

' Function will take in the number of characters in the string, as well as the optional parameter of chars to use in the random string
    Private Function RandomString(ByVal Chars_In_String As Integer, Optional ByVal Valid_Chars As String = "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM")
        ' Create a string to hold the resulting random string
        Dim ReturnMe As String = ""

        ' Loop variable
        Dim i As Integer = 0

        ' Run while loop while i is less than the desired number of Chars_In_String
        While i < Chars_In_String
            ' Each time through, add to ReturnMe (selecting a random character out of the string of all valid characters)
            ReturnMe += Valid_Chars(random.[Next](0, Valid_Chars.Length))
        End While

        ' Return the value of ReturnMe
        Return ReturnMe
    End Function
    ' Create a new instance of the Random class, using a time-dependant default seed value
    Dim random As New Random()

    private static string RandomString(int Chars_In_String)
    {
        // Create a string to contain all valid characters (in this case, just letters)
        string all = "qwertyuiopasdfghjklzxcvbnmQWERTYIOPASDFGHJKLZXCVBNM";

        // Create a variable that will be returned, it will hold the random string
        string ReturnMe = "";

        // Run for loop until we have reached the desired number of Chars_In_String
        for (int i = 0; i < Chars_In_String; i++)
        {
            // Each time through, add to ReturnMe (selecting a random character out of the string of all valid characters)
            ReturnMe += all[random.Next(0, all.Length)];
        } 

        // Return the value of ReturnMe
        return ReturnMe;
    }
    // Create a new instance of the Random class, using a time-dependant default seed value
    static Random random = new Random();

同样，这也没什么不同，但我真正努力的部分是VB代码第12行和C代码第13行之间的转换

我真的不知道如何将它转换为VB.NET，正如我所说的，我对它的了解非常有限，所以我使用了一个在线转换器。联机转换器的结果运行时没有错误，但是当我尝试调用该函数时，没有出现任何字符串

简而言之，此C代码运行良好： ReturnMe+=all[random.Next0，all.Length]

但是，此VB.NET代码不起作用： ReturnMe+=有效字符随机。[下一步]0，有效字符长度

---

如何修复VB.NET代码？

您的函数中存在一些问题：

' Function will take in the number of characters in the string, as well as the optional parameter of chars to use in the random string
    Private Function RandomString(ByVal Chars_In_String As Integer, Optional ByVal Valid_Chars As String = "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM")
        ' Create a string to hold the resulting random string
        Dim ReturnMe As String = ""

        ' Loop variable
        Dim i As Integer = 0

        ' Run while loop while i is less than the desired number of Chars_In_String
        While i < Chars_In_String
            ' Each time through, add to ReturnMe (selecting a random character out of the string of all valid characters)
            ReturnMe += Valid_Chars(random.[Next](0, Valid_Chars.Length))
        End While

        ' Return the value of ReturnMe
        Return ReturnMe
    End Function
    ' Create a new instance of the Random class, using a time-dependant default seed value
    Dim random As New Random()

    private static string RandomString(int Chars_In_String)
    {
        // Create a string to contain all valid characters (in this case, just letters)
        string all = "qwertyuiopasdfghjklzxcvbnmQWERTYIOPASDFGHJKLZXCVBNM";

        // Create a variable that will be returned, it will hold the random string
        string ReturnMe = "";

        // Run for loop until we have reached the desired number of Chars_In_String
        for (int i = 0; i < Chars_In_String; i++)
        {
            // Each time through, add to ReturnMe (selecting a random character out of the string of all valid characters)
            ReturnMe += all[random.Next(0, all.Length)];
        } 

        // Return the value of ReturnMe
        return ReturnMe;
    }
    // Create a new instance of the Random class, using a time-dependant default seed value
    static Random random = new Random();

您缺少while循环变量的增量，这样函数将失败并出现OutOfMemoryException 即使在C情况下，也不应该连接字符串。改用StringBuilder。 这个代码应该有效

Private Shared Function RandomString(ByVal Chars_In_String As Integer, Optional ByVal Valid_Chars As String = "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM") As String
    Dim sb As StringBuilder = new StringBuilder()

    Dim i As Integer = 0
    Dim random As New Random()

    While i < Chars_In_String
        sb.Append(Valid_Chars(random.[Next](0, Valid_Chars.Length)))
        i = i + 1
    End While

    Return sb.ToString()
End Function

---

您的职能中有几个问题：

' Function will take in the number of characters in the string, as well as the optional parameter of chars to use in the random string
    Private Function RandomString(ByVal Chars_In_String As Integer, Optional ByVal Valid_Chars As String = "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM")
        ' Create a string to hold the resulting random string
        Dim ReturnMe As String = ""

        ' Loop variable
        Dim i As Integer = 0

        ' Run while loop while i is less than the desired number of Chars_In_String
        While i < Chars_In_String
            ' Each time through, add to ReturnMe (selecting a random character out of the string of all valid characters)
            ReturnMe += Valid_Chars(random.[Next](0, Valid_Chars.Length))
        End While

        ' Return the value of ReturnMe
        Return ReturnMe
    End Function
    ' Create a new instance of the Random class, using a time-dependant default seed value
    Dim random As New Random()

    private static string RandomString(int Chars_In_String)
    {
        // Create a string to contain all valid characters (in this case, just letters)
        string all = "qwertyuiopasdfghjklzxcvbnmQWERTYIOPASDFGHJKLZXCVBNM";

        // Create a variable that will be returned, it will hold the random string
        string ReturnMe = "";

        // Run for loop until we have reached the desired number of Chars_In_String
        for (int i = 0; i < Chars_In_String; i++)
        {
            // Each time through, add to ReturnMe (selecting a random character out of the string of all valid characters)
            ReturnMe += all[random.Next(0, all.Length)];
        } 

        // Return the value of ReturnMe
        return ReturnMe;
    }
    // Create a new instance of the Random class, using a time-dependant default seed value
    static Random random = new Random();

您缺少while循环变量的增量，这样函数将失败并出现OutOfMemoryException 即使在C情况下，也不应该连接字符串。改用StringBuilder。 这个代码应该有效

Private Shared Function RandomString(ByVal Chars_In_String As Integer, Optional ByVal Valid_Chars As String = "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM") As String
    Dim sb As StringBuilder = new StringBuilder()

    Dim i As Integer = 0
    Dim random As New Random()

    While i < Chars_In_String
        sb.Append(Valid_Chars(random.[Next](0, Valid_Chars.Length)))
        i = i + 1
    End While

    Return sb.ToString()
End Function

---

它与字符串索引操作无关，它是正确的。您只是忘记了增加循环计数器。使用For关键字：

    Dim ReturnMe As String = ""
    For i As Integer = 1 To Chars_In_String
        ReturnMe += Valid_Chars(random.Next(0, Valid_Chars.Length))
    Next
    Return ReturnMe

---

如果字符串中的字符变得更大，那么字符串生成器将是明智的。除非此代码位于模块内，否则请使用Shared关键字。

它与字符串索引操作无关，它是正确的。您只是忘记了增加循环计数器。使用For关键字：

    Dim ReturnMe As String = ""
    For i As Integer = 1 To Chars_In_String
        ReturnMe += Valid_Chars(random.Next(0, Valid_Chars.Length))
    Next
    Return ReturnMe

---

如果字符串中的字符变得更大，那么字符串生成器将是明智的。除非此代码位于模块内，否则请使用Shared关键字。

@HillBilly.Developer:只是猜测，但可能是因为1个GUID不保证是随机的，2个GUID是固定长度的。@HillBilly.Developer:只是猜测，但可能是因为1个GUID不保证是随机的，2个GUID是固定长度的。