随机生成字符串 [英] Random Generation string

问题描述

大家好，



我想生成固定长度的随机字符串。代码如下。

Hi All,

I would like to generate Random string of fixed length.The code is below.

Private Shared Function RandomString(Size As Integer) As String
        Dim input As String = "abcdefghijklmnopqrstuvwxyz0123456789"
        Dim chars = Enumerable.Range(0, Size).[Select](Function(x) input(Random.[Next](0, input.Length)))
        Return New String(chars.ToArray())
    End Function

但我收到错误

But I receive an error of

Quote：

重载决策失败，因为没有可访问的'Select'可以使用这些参数调用：

扩展方法'公共函数选择（Of TResult）（selector As System.Func（Of Integer） ，Integer，TResult））作为System.Collections.Generic.IEnumerable（Of TResult）'在'System.Linq.Enumerable'中定义：嵌套函数没有与委托'System.Func兼容的签名（Of Integer，Integer） ，TResult）'。

扩展方法'Public Function Select（Of TResult）（selector As System.Func（Of Integer，Integer，TResult））As System.Collections.Generic.IEnumerable（Of TResult） '定义在'System.Linq.Enumerable'中：无法从这些参数推断出类型参数的数据类型。明确指定数据类型可能会纠正此错误。

Overload resolution failed because no accessible 'Select' can be called with these arguments:
Extension method 'Public Function Select(Of TResult)(selector As System.Func(Of Integer, Integer, TResult)) As System.Collections.Generic.IEnumerable(Of TResult)' defined in 'System.Linq.Enumerable': Nested function does not have a signature that is compatible with delegate 'System.Func(Of Integer, Integer, TResult)'.
Extension method 'Public Function Select(Of TResult)(selector As System.Func(Of Integer, Integer, TResult)) As System.Collections.Generic.IEnumerable(Of TResult)' defined in 'System.Linq.Enumerable': Data type(s) of the type parameter(s) cannot be inferred from these arguments. Specifying the data type(s) explicitly might correct this error.

问候

Sreejith

Regards
Sreejith

推荐答案

试试这个：

Try this:

Private Shared chars As String = "abcdefghijklmnopqrstuvwxyz0123456789"
Private random As New Random()
Private Function RandomString(size As Integer) As String
    Return New String(Enumerable.Repeat(chars, size).[Select](Function(s) s(random.[Next](s.Length))).ToArray())
End Function

随机需要初始化！请参阅： Ranodm Class（System） [< a href =https://msdn.microsoft.com/en-us/library/system.random%28v=vs.110%29.aspxtarget =_ blanktitle =New Window> ^ ]



这也有效：

Random needs to be intialized! Please see: Ranodm Class (System)[^]

This works as well:

Private Function RandomString(size As Integer) As String

	Dim input As String = "abcdefghijklmnopqrstuvwxyz0123456789"
	Dim r As New Random
	Dim qry = Enumerable.Range(0, Size).[Select](Function(x) input(r.Next(0, input.Length)))
	Return New String(qry.ToArray())
   
End Function

使用和结果：

Usage and result:

Dim a As String = RandomString(55)
'result: y0lchxdvh8yaz73tbu1q0h6uptpkm19ldso8ozm64pnk7bvum86uz9e

好的，似乎有一个网站错误破坏了VB代码。

让我们看看我们是否可以得到它可读：

OK, there seems to be a site bug which is corrupting the VB code.
Let's see if we can get it readable:

Private Shared chars As String = "abcdefghijklmnopqrstuvwxyz0123456789"
Private random As New Random()
Private Function RandomString(size As Integer) As String
    Return New String(Enumerable.Repeat(chars, size). [Select]

(Function(s) s( random. [Next]

(s.Length))) .ToArray())
End Function

将这些位组合成一行！

Assemble the bits into a single line!

这篇关于随机生成字符串的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！