Generate random code

Using system;
Using system. Collections. Generic;
Using system. Text. regularexpressions;
Using system. text;

Namespace insapp. Word
{
/// <Summary>
/// String createrandomcode (INT codecount) generates random numbers and letters Based on the length
/// Bool tofilter (string thepara) detects invalid characters. If the parameter is null or contains invalid characters, false is returned. Otherwise, true is returned.
/// Bool checknumber (string getnum) determines whether it is in numeric format
/// Bool checknumberregx (string getnum) determines whether it is a positive or negative number with decimals
/// Bool checknullstr (string getstr) returns true if it is null | false
/// </Summary>
Public class createcode
{

# Region generates random numbers and letters. codecount is the length to be generated.
/// <Summary>
/// Generate random numbers and letters
/// </Summary>
/// <Param name = "codecount"> codecount is the expected length </param>
/// <Returns> </returns>
Public String createrandomcode (INT codecount) // codecount is the length to be generated
{
String allchar = ";
String [] allchararray = allchar. Split (',');
String randomcode = "";
Random Rand = new random ();
Int temp =-1;
For (INT I = 0; I <codecount; I ++)
{
If (temp! =-1)
{
Rand = new random (I * temp * (INT) datetime. Now. ticks ));
}
Int T = Rand. Next (0, 10 );

Temp = T;
Randomcode + = allchararray [T];
}
Return randomcode;
}
# Endregion

# Region determine whether the digit format is used
/// <Summary>
/// Determine whether the digit format is used
/// </Summary>
/// <Param name = "getnum"> </param>
Public bool checknumber (string getnum)
{

RegEx r = new RegEx (@ "^ [0-9] + $ ");
If (R. ismatch (getnum ))
{
Return true;
}
Else
{
Return false;
}
}
# Endregion

# Region checks invalid characters to prevent SQL Injection

/// <Summary>
/// Check for invalid characters to prevent SQL Injection
/// If the parameter is null, false is returned.
/// If the parameter contains invalid characters, false is returned.
//// Otherwise, true is returned.
/// </Summary>
/// <Param name = "thepara"> </param>
/// <Returns> </returns>
Public bool tofilter (string thepara)
{
String [] badcode = new string [] {"'", "\" "," EXEC "," cmd ","> "," <"," and ", "= ","\\",";"};
Try
{
If (checknullstr (thepara) = false) // If the parameter is null, false is returned.
{
Throw new exception ("the parameter is null ");
}
Else
{
For (INT I = 0; I <badcode. length; I ++)
{
If (thepara. indexof (badcode [I])> 0)
{
Throw new exception ("contains invalid characters ");
}
}
}
Return true;
}
Catch
{
Return false;
}

}
# Endregion

# Region bool checknullstr (string getstr)
/// <Summary>
/// Getstr
/// </Summary>
/// <Param name = "getstr"> value to be checked </param>
/// <Param name = "getshow"> function description of this field: name, sex </param>
Public bool checknullstr (string getstr)
{
Try
{
If (getstr = NULL | getstr = "" | getstr. Length <1)
{
Return false;
}
Else
{
Return true;
}
}
Catch
{
Return false;
}

}
# Endregion

# Region bool checknumberregx (string getnum) Regular Expression to determine whether positive or negative numbers contain Decimals
/// <Summary>
/// Determine whether the digit format is used
/// </Summary>
/// <Param name = "getnum"> </param>
Public bool checknumberregx (string getnum)
{
// ^ [+-]? \ D + (\. \ D + )? $ Plus or minus digits include decimal digits ^ \ D + (\. \ D + )? $
RegEx r = new RegEx (@ "^ \ D + (\. \ D + )? $ ");
If (R. ismatch (getnum ))
{
Return true;
}
Else
{
Return false;
}

}
# Endregion

# Region uses C # to intercept a string of the specified length.
/// <Summary>
// Characters accepted by S
/// L Length
/// </Summary>
/// <Param name = "S"> </param>
/// <Param name = "L"> </param>
/// <Returns> </returns>
Public static string cutstr (string S, int L)
{
String temp = s;
If (RegEx. Replace (temp, "[\ u4e00-\ u9fa5]", "ZZ", regexoptions. ignorecase). Length <= L)
{
Return temp;
}
For (INT I = temp. length; I> = 0; I --)
{
Temp = temp. substring (0, I );
If (RegEx. Replace (temp, "[\ u4e00-\ u9fa5]", "ZZ", regexoptions. ignorecase). Length <= L-3)
{
Return temp + "";
}
}
Return "";
}
# Endregion

# Region random numbers and letters
/// <Summary>
/// Random numbers and letters
/// </Summary>
/// <Param name = "N"> generation length </param>
/// <Returns> </returns>
Public static string rand_number_az_code (int n)
{
Char [] arrchar = new char [] {
'A', 'B', 'D', 'C', 'E', 'E', 'F', 'G', 'h', 'I', 'J ', 'k', 'l', 'M', 'n', 'P', 'R', 'Q', 's', 't', 'U ', 'V', 'w', 'z', 'y', 'x ',
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9 ',
'A', 'B', 'C', 'D', 'E', 'E', 'F', 'G', 'h', 'I', 'J ', 'k', 'l', 'M', 'n', 'Q', 'P', 'R', 't', 's', 'V ', 'U', 'w', 'x', 'y', 'Z'
};

Stringbuilder num = new stringbuilder ();

Random RND = new random (datetime. Now. millisecond );
For (INT I = 0; I <n; I ++)
{
Num. append (arrchar [RND. Next (0, arrchar. Length)]. tostring ());

}

Return num. tostring ();
}
# Endregion

# region letter random number
///

// letter random number
///
/// generation length
//
Public static string randletter (int n)
{< br> char [] arrchar = new char [] {
'A', 'B', 'D', 'C', 'E ', 'F', 'G', 'h', 'I', 'J', 'k', 'l', 'M', 'n', 'P ', 'R', 'Q', 's', 't', 'U', 'V', 'w', 'z', 'y', 'x ',
'A', 'B', 'C', 'D', 'E', 'E', 'F', 'G', 'h', 'I ', 'J', 'k', 'l', 'M', 'n', 'Q', 'P', 'R', 't','s ', 'V', 'U', 'w', 'x', 'y', 'z'
};

Stringbuilder num = new stringbuilder ();

Random RND = new random (datetime. Now. millisecond );
For (INT I = 0; I <n; I ++)
{
Num. append (arrchar [RND. Next (0, arrchar. Length)]. tostring ());

}

Return num. tostring ();
}
# Endregion

# Region date Random Function
/// <Summary>
/// Date Random Function
/// </Summary>
/// <Param name = "ra"> length </param>
/// <Returns> </returns>
Public static string daterndname (random RA)
{
Datetime d = datetime. now;
String S = NULL, Y, M, DD, H, mm, SS;
Y = D. year. tostring ();
M = D. Month. tostring ();
If (M. Length <2) M = "0" + m;
Dd = D. Day. tostring ();
If (DD. Length <2) dd = "0" + dd;
H = D. Hour. tostring ();
If (H. Length <2) H = "0" + h;
Mm = D. Minute. tostring ();
If (Mm. Length <2) Mm = "0" + mm;
Ss = D. Second. tostring ();
If (ss. Length <2) Ss = "0" + SS;
S + = Y + M + dd + H + mm + SS;
S + = Ra. Next (100,999). tostring ();
Return S;
}
# Endregion

# Region generation guid
/// <Summary>
/// Generate guid
/// </Summary>
/// <Returns> </returns>
Public static string getguid ()
{
System. guid G = system. guid. newguid ();
Return G. tostring ();
}
# Endregion

}

 

}