title: I want Regex validate mobile and phone number in given format
body: <p>I want user can only enter mobile/phone number in given format.</p>
  
  <p>+1234567891 > when + is used exact after plus user cannot enter 0 or 00 and also if + is used after + only 10 to 14 digits are allowed.</p>
  
  <p>01234567891 > when user enter single 0 then user must enter 10 digits only after 0.</p>
  
  <p>00123456789 > when user enter double 00 then after that user cannot enter 3rd 0 exact after double 00 and also user must enter 10 to 14 digits after double 00.</p>
  
  <p>My code is this any one can help me please?   </p>
  
  <pre><code>string mob = txtmobile.Text.Trim();
  Regex plus = new Regex("^[+]?&lt;!(0|00)[0-9]{10,14}$");
  Regex zero = new Regex("^[0]{1}[0-9]{10}$");
  Regex zeroes = new Regex("^[0]{2}[^0][0-9]{10,14}$");
  
          if (!plus.IsMatch(mob))
          {
              if (!zero.IsMatch(mob))
              {
                  if (!zeroes.IsMatch(mob))
                  {
                      lblmobile.Text = "*Mobile number must be correct format";
                      lblmobile.Visible = true;
                      flg = false;
                  }
              }
          }
  </code></pre>