我已经开发了一个随机字符串生成器,但它的行为并不像我所希望的那样。我的目标是能够运行两次,并生成两个不同的四字符随机字符串。但是,它只生成一个四个字符的随机字符串两次。
下面是代码和输出示例:
private string RandomString(int size)
{
StringBuilder builder = new StringBuilder();
Random random = new Random();
char ch;
for (int i = 0; i < size; i++)
{
ch = Convert.ToChar(Convert.ToInt32(Math.Floor(26 * random.NextDouble() + 65)));
builder.Append(ch);
}
return builder.ToString();
}
// get 1st random string
string Rand1 = RandomString(4);
// get 2nd random string
string Rand2 = RandomString(4);
// create full rand string
string docNum = Rand1 + "-" + Rand2;
...输出如下:UNTE-UNTE
...但它应该看起来像这个UNTE-FWNU
如何确保两个明显随机的字符串?
这个解决方案是Random类的扩展。
使用
class Program
{
private static Random random = new Random();
static void Main(string[] args)
{
random.NextString(10); // "cH*%I\fUWH0"
random.NextString(10); // "Cw&N%27+EM"
random.NextString(10); // "0LZ}nEJ}_-"
random.NextString(); // "kFmeget80LZ}nEJ}_-"
}
}
实现
public static class RandomEx
{
/// <summary>
/// Generates random string of printable ASCII symbols of a given length
/// </summary>
/// <param name="r">instance of the Random class</param>
/// <param name="length">length of a random string</param>
/// <returns>Random string of a given length</returns>
public static string NextString(this Random r, int length)
{
var data = new byte[length];
for (int i = 0; i < data.Length; i++)
{
// All ASCII symbols: printable and non-printable
// data[i] = (byte)r.Next(0, 128);
// Only printable ASCII
data[i] = (byte)r.Next(32, 127);
}
var encoding = new ASCIIEncoding();
return encoding.GetString(data);
}
/// <summary>
/// Generates random string of printable ASCII symbols
/// with random length of 10 to 20 chars
/// </summary>
/// <param name="r">instance of the Random class</param>
/// <returns>Random string of a random length between 10 and 20 chars</returns>
public static string NextString(this Random r)
{
int length = r.Next(10, 21);
return NextString(r, length);
}
}
还有另一个版本:我在测试中使用这种方法生成随机的伪股票代码:
Random rand = new Random();
Func<char> randChar = () => (char)rand.Next(65, 91); // upper case ascii codes
Func<int,string> randStr = null;
randStr = (x) => (x>0) ? randStr(--x)+randChar() : ""; // recursive
用法:
string str4 = randStr(4);// generates a random 4 char string
string strx = randStr(rand.next(1,5)); // random string between 1-4 chars in length
你可以重新定义randChar函数,使用一个“允许的”字符数组,而不是ascii码:
char[] allowedchars = {'A','B','C','1','2','3'};
Func<char> randChar = () => allowedchars[rand.Next(0, allowedchars.Length-1)];
对于随机字符串生成器:
#region CREATE RANDOM STRING WORD
char[] wrandom = {'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','R','S','T','U','V','X','W','Y','Z'};
Random random = new Random();
string random_string = "";
int count = 12; //YOU WILL SPECIFY HOW MANY CHARACTER WILL BE GENERATE
for (int i = 0; i < count; i++ )
{
random_string = random_string + wrandom[random.Next(0, 24)].ToString();
}
MessageBox.Show(random_string);
#endregion