Check if string starts with specific string in C# and VB.Net

Hi irshad1231,

Check this example. Now please take its reference and correct your code.

C#

string mobileno = "966123456789";
string finalmobileno = "";
if (mobileno.StartsWith("966")) //starting with 966
{
    finalmobileno = Regex.Replace(mobileno, "^966", "", RegexOptions.IgnoreCase); // Replace starting 966.
}
Response.Write(finalmobileno.ToString() + "<br/>");

string iqamano = "0123456789";
if (iqamano.StartsWith("0")) //starting with 0
{
    finalmobileno = Regex.Replace(iqamano, "^0", "", RegexOptions.IgnoreCase); // Replace starting 0.
}
Response.Write(finalmobileno.ToString());

VB.Net

Dim mobileno As String = "966123456789"
Dim finalmobileno As String = ""
If mobileno.StartsWith("966") Then 'starting with 966
    finalmobileno = Regex.Replace(mobileno, "^966", "", RegexOptions.IgnoreCase) 'Replace starting 966.
End If
Response.Write(finalmobileno.ToString() & "<br/>")
Dim iqamano As String = "0123456789"

If iqamano.StartsWith("0") Then 'starting with 0
    finalmobileno = Regex.Replace(iqamano, "^0", "", RegexOptions.IgnoreCase) 'Replace starting 0.
End If
Response.Write(finalmobileno.ToString())

Output

123456789

123456789

Try this without Regex simple and easy.

string mobileno = "966123456789";
string finalmobileno = "";
if (mobileno.StartsWith("966")) //starting with 966
{
    finalmobileno = mobileno.Substring(mobileno.IndexOf("966") +3);
}
lbl_mobile.Text = finalmobileno.ToString();

string iqamano = "0123456789";
if (iqamano.StartsWith("0")) //starting with 0
{
    finalmobileno = iqamano.Substring(iqamano.IndexOf("0") +1);
}
lbl_mobile.Text = finalmobileno.ToString();

I'm doing this as below. It's working.

if (mobileno.StartsWith("966"))
{
    lbl_mobile.Text = mobileno.Remove(0, 3);
}
else
{
    lbl_mobile.Text = mobileno.Remove(0, 1);
}