Random Number

Mittal Sejpal

15y2.9k.NET

I need to generated Random String including numbers,char,alphanumneric etc...

thanks i advance

7 Replies

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Vulpes15y ago
Accepted answer
It sounds like request validation is flagging that as a possible script attack because the random string looks like it could include unencoded HTML.

To prevent that I'd stick to alphanumeric characters or at the very least don't use < and > :

static string GetRandomString(int length)
{
char[] chars = new char[length];
for (int i = 0; i < length; i++)
{
int j;

do
{
j = rand.Next(32, 127);
}
while(j == 60 || j == 62); // don't use < or >

chars[i] = (char)j;
return new string(chars);
}
}
Mahesh Chand15y ago
Mittal,
No need to make text colored and size 50. I am sure Vulpes has answered you. Also, see lot of articles in the right side of this.

Thanks! Keep the forums tidy!
Bharat Bhushan15y ago
see this link

http://howtouseasp.net/alpha-numeric-digits-numbers-for-password-asp-net/
Mittal Sejpal15y ago
A potentially dangerous Request.Form value was detected from the client (TextBox2="HBf@gWjU#)z}m3"). after 3 or 4 times it give like this error
Prabhu Raja15y ago
Hi Mittal, follow this Source Code link to generate random number.

http://www.obviex.com/Samples/Password.aspx
Vulpes15y ago
If 'cryptographic strength' randomness is not needed, here's a simpler approach using the Random class.

The random string may contain any character in the ASCII range from 32 (space) to 126 (tilde) inclusive:

using System;

class Program
{
static Random rand = new Random();

static void Main()
{
string s = GetRandomString(10);
Console.WriteLine(s);
Console.ReadKey();
}

static string GetRandomString(int length)
{
char[] chars = new char[length];
for (int i = 0; i < length; i++) chars[i] = (char)rand.Next(32, 127);
return new string(chars);
}
}
Satyapriya Nayak15y ago
Hi Mittal,

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Security.Cryptography;
namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {


        }
        private string RandomString(int StrLength)
        {

            string CharsList = "abcdefghijklmnopqrstuvwxyz1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ?><*";

            char[] chars = CharsList.ToCharArray();

            RNGCryptoServiceProvider cryptoGen = new RNGCryptoServiceProvider();

            byte[] ByteData = new byte[StrLength];

            cryptoGen.GetBytes(ByteData);

            StringBuilder ResultStr = new StringBuilder();

            foreach (byte byt in ByteData)
            {

                ResultStr.Append(chars[byt % chars.Length]);

            }

            return ResultStr.ToString();

        }

        private void button1_Click(object sender, EventArgs e)
        {
            label1.Text = RandomString(8);
        }

    }
}

Thanks
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Random Number

A potentially dangerous Request.Form value was detected from the client (TextBox2="HBf@gWjU#)z}m3"). after 3 or 4 times it give like this error