function validateDate(strValue) {
  var objRegExp  = /(^(((((0[1-9])|(1\d)|(2[0-8]))-((0[1-9])|(1[0-2])))|((31-((0[13578])|(1[02])))|((29|30)-((0[1,3-9])|(1[0-2])))))-((20[0-9][0-9]))|(29-02-20(([02468][048])|([13579][26]))))$)/;

  return objRegExp.test(strValue);
}

function makeDefinitive(id, btn) {
  $("#dialog-confirm-def").dialog({
    resizable: false,
    height:150,
    modal: true,
    buttons: {
      "Ok": function() {
        __doPostBack(btn, '');
        $(this).dialog("close");
      },
      "Annuleren": function() {
        $(this).dialog("close");
      }
    }
  });
  
  return false;
}

function validateInteger(strValue) {
  var objRegExp  = /(^-?\d\d*$)/;

  //check for integer characters
  return objRegExp.test(strValue);
}

function validateNegativeInteger(el) {
  var objRegExp  = /(^-?\d\d*$)/;
  var strValue = el.value;

  if (strValue > 0) {
    strValue = 0 - strValue;
    el.value = strValue;
  }

  //check for integer characters
  return objRegExp.test(strValue) && strValue < 0;
}

function checkInt(evt, allowDash) {
  try {
    var charCode = ( evt.which ) ? evt.which : event.keyCode;
    
    if (allowDash == true) {
      return (( charCode >= 48 && charCode <= 57 ) || (charCode == 8) || (charCode == 45));
    } else {
      return (( charCode >= 48 && charCode <= 57 ) || (charCode == 8));
    }
  } catch(e) {
    return evt;
  }
}