ASP.NET Validation Tips and Tricks (Part1)

using System.Text.RegularExpressions;
 
public class IPAddressTextBox: RegExTextBox
{
public IPAddressTextBox() 
{
InitializeComponent();
this.ValidationExpression = @"^((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9])\.){3}(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9])$";
this.ErrorMessage = "The IP address must be in the form of 111.111.111.111";
}

using System.Text.RegularExpressions;
 
public class SsnTextBox: RegExTextBox
{
public SsnTextBox() 
{ 
InitializeComponent();
this.ValidationExpression = @"^\d{3}-\d{2}-\d{4}$";
this.ErrorMessage = "The social security number must be in the form of 555-55-5555";
}
}

function MaxNumber(id,size)
{
if(id!=null)
{
var no =id.length;
if(no>=size)
{
alert("Maximum length exceeds");
event.returnValue=false;
return false;
}
else
{
return true;
}
}//End of IF
 
}//End Of Funciton

Public Function ValidIP(ByVal addr As String) As Boolean
'create our match pattern
Dim pat As String = "^([1-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(\." & _
"([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3}$"
Dim check As New Text.RegularExpressions.Regex(pat)
'boolean variable to hold the status
Dim valid As Boolean = False
If addr = "" Then
valid = False
Else
valid = check.IsMatch(addr, 0)
End If
'return the results
Return valid
End Function
55.255

System.Text.RegularExpressions Namespace
 
using System.Text.RegularExpressions;
 
public bool IsUppercase(string str) //string to check
{
bool upper; //to hold return value
string pattern = "[a-z]"; //variable to hold the search pattern
try
{
Regex AllCaps = new Regex(pattern);
if (AllCaps.IsMatch(str))
{
upper = false;
}
upper = true;
}
catch
{
upper = false;
}
return upper;
}