function cleartxtFlatRate(){
   var radioObj = document.forms['aspnetForm'].rdoStandType;
   var radioLength = radioObj.length;
 
    if(radioObj[radioLength-1].checked) {
        document.getElementById("txtFlatRate").style.display="block";
        document.getElementById("lbltxtFlatRate").style.display="block";
    } else {
        document.getElementById("txtFlatRate").value="";
        document.getElementById("txtFlatRate").style.display="none";
        document.getElementById("lbltxtFlatRate").style.display="none";
    }
}

function validateTxtFlatRate(){
        
    if (document.getElementById("txtFlatRate").style.display == 'block'){
        //var reg=/^[-+]?[0-9]+(\.[0-9]+)?$/;
        var reg =  /^\s*()?((\d+(\.\d+)?)|(\.\d+))\s*$/;
        var str =  document.getElementById("txtFlatRate").value;
        if (reg.test(str) == false || str == 0){
            alert ("Please enter a numeric value in the flat rate box.");
            document.getElementById("txtFlatRate").focus();
            return false;
        } else { 
            return true;
        }
    }
}