Textbox allows only Numbers with dots and spaces

Design:

<asp:Content ID="Content1" ContentPlaceHolderID="contentPlaceHolder" Runat="Server">
<script type="text/javascript">
//Numbers and dots
  function isNumberKey(evt) {
      var charCode = (evt.which) ? evt.which : event.keyCode
      if (charCode != 46 && (charCode < 48 || charCode > 57)) {
          return false;
      }
      else {
          return true;
      }
  }        

//Number and spaces
function isNumberKey1(evt) {
      var charCode = (evt.which) ? evt.which : event.keyCode
      if (charCode != 32 && (charCode < 48 || charCode > 57)) {
          return false;
      }
      else {
          return true;
      }
  }          
</script>
<asp:TextBox ID="txtMFGQty" runat="server" Height="22px" Width="224px" onkeypress= "return isNumberKey(event)"
                        MaxLength="12"></asp:TextBox>

<asp:TextBox ID="txtPhoneNo" onkeypress= "return isNumberKey1(event)" runat="server" Width="200px" MaxLength="12"></asp:TextBox>