function leftTrim(sString)
{
    while (sString.substring(0,1) == ' ')
    {
        sString = sString.substring(1, sString.length);
    }
    return sString;
}
 
function rightTrim(sString)
{
    while (sString.substring(sString.length-1, sString.length) == ' ')
    {
        sString = sString.substring(0,sString.length-1);
    }
    return sString;
}
 
function trim(sString)
{
    while (sString.substring(0,1) == ' ')
    {
        sString = sString.substring(1, sString.length);
    }
    while (sString.substring(sString.length-1, sString.length) == ' ')
    {
        sString = sString.substring(0,sString.length-1);
    }
    return sString;
}
 
function pre_check()
{
    document.logonform.logon_id.value = trim(document.logonform.logon_id.value);
    document.logonform.password.value = trim(document.logonform.password.value);
 
    if( trim(document.logonform.logon_id.value).length == 0)
    {
        document.logonform.logon_id.value = "";
        alert("please enter [Logon ID]");
        document.logonform.logon_id.focus();
        return false;
    }
 
    if( trim(document.logonform.password.value).length == 0)
    {
        document.logonform.password.value = "";
        alert("please enter [Password]");
        document.logonform.password.focus();
        return false;
    }
 
    document.logonform.submit()
}
 
function whenfocus(ob, default_value)
{
    if( ob.value == default_value ) ob.value="";
}