var d = document;

function hdm ( i ){
	if ( i == 1 ) {
		d.getElementById( 'hdm_b_01' ).style.background = 'url(images/hdm_01_h.jpg) no-repeat';
		d.getElementById( 'hdm_b_02' ).style.background = 'url(images/hdm_02.jpg) no-repeat';
		d.getElementById( 'hdm_b_03' ).style.background = 'url(images/hdm_03.jpg) no-repeat';
		d.getElementById( 'hdm_01' ).style.display = '';
		d.getElementById( 'hdm_02' ).style.display = 'none';
		d.getElementById( 'hdm_03' ).style.display = 'none';
	}else if ( i == 2 ) {
		d.getElementById( 'hdm_b_01' ).style.background = 'url(images/hdm_01.jpg) no-repeat';
		d.getElementById( 'hdm_b_02' ).style.background = 'url(images/hdm_02_h.jpg) no-repeat';
		d.getElementById( 'hdm_b_03' ).style.background = 'url(images/hdm_03.jpg) no-repeat';
		d.getElementById( 'hdm_01' ).style.display = 'none';
		d.getElementById( 'hdm_02' ).style.display = '';
		d.getElementById( 'hdm_03' ).style.display = 'none';
	}else if ( i == 3 ) {
		d.getElementById( 'hdm_b_01' ).style.background = 'url(images/hdm_01.jpg) no-repeat';
		d.getElementById( 'hdm_b_02' ).style.background = 'url(images/hdm_02.jpg) no-repeat';
		d.getElementById( 'hdm_b_03' ).style.background = 'url(images/hdm_03_h.jpg) no-repeat';
		d.getElementById( 'hdm_01' ).style.display = 'none';
		d.getElementById( 'hdm_02' ).style.display = 'none';
		d.getElementById( 'hdm_03' ).style.display = '';
	}
}


function zhuxicheng ( i ){
	if ( i == 1 ) {
		d.getElementById('zhu').style.display="";
		d.getElementById('zhu_1').style.display="none";	
	}
	else
	if ( i == 2 )	{
				d.getElementById('zhu_1').style.display="";	
				d.getElementById('zhu').style.display="none";
					}
}


/*nnnn*/
function validate_required(field,alerttxt)
{
with (field)
  {
  if (value==null||value=="")
    {alert(alerttxt);return false}
  else {return true}
  }
}

function validate_form(thisform)
{
with (thisform)
  {
  if (validate_required(content,"内容不能为空！")==false)
    {email.focus();return false}
  }
}