var current_time_tb;
function MyShowTimeBlock(tb){
    current_time_tb=tb;
    var curr_v=$(tb).value;
    var h=0,m=0,type=0;
    for(var i=0;i<curr_v.length;i++)
        if(curr_v.charAt(i)==':') type++;
        else{
            if(type==0) h=10*h+(curr_v.charAt(i)-'0');
            else m=10*m+(curr_v.charAt(i)-'0');
        }
    if(h>=0 && h<=23) $('time_block_h').value=h;
    if(m>=0 && m<60) $('time_block_m').value=(m<10?'0':'')+m;
}
function MyCloseTimeBox(){
    var val='';
    var c1=$('time_block_h').value;   
    var c2=$('time_block_m').value;
    if((c1*2)/2==c1 && (c2*2)/2==c2 && c1>=0 && c1<24 && c2>=0 && c2<60)
        $(current_time_tb).value=c1+':'+(c2<10?'0':'')+(1*c2);
    else $(current_time_tb).value='';                
}