function resetAll()
{//清空所有文本框以及與之有關(guān)的圖片顯示
	if(!confirm('Are you sure to clear?')) 
	{
    	return false;
    }
	document.getElementById('up_form').reset();
	document.getElementById("message_up_pic").innerHTML='';
	document.getElementById('img_div').style.display='none';
    document.getElementById('img_show').src= '';
    
}

function submitForm()
{//實現(xiàn)提交功能
     if (submitEnable())
     {
       document.getElementById('up_form').submit();
     }
}

function submitEnable()
{
var photoType = document.getElementById('photoType').value;
	var photoName = document.getElementById('photoName').value;
	var up_file = document.getElementById('up_file').value;
	if ( !isNotNull(photoType)) 
     {
    	return false;
    }
	if ( !isNotNull(photoName))
     {
        document.getElementById('photoName_span').innerHTML='!';
    	return false;
    }
	if ( !isNotNull(up_file))
     {
     document.getElementById('up_file_span').innerHTML='.gif .jpg';
    	return false;
    }
	return true;
}

//begin showImg
function showImg()
{
	document.getElementById("message_up_pic").innerHTML='';
	if (!checkImg(document.getElementById('up_file').value))
    {
		document.getElementById('up_form').reset();
		return false;
	}
	document.getElementById('img_div').style.display='block'
	document.getElementById('img_show').src= document.getElementById('up_file').value;
	return true;
}

function checkImg(str)
{
	var index = str.lastIndexOf('.') ;
	if (index > -1)
	{
		var sub = str.substring(index);
		return match(sub);
	}
	return match(str);
}

function match(str)
{
	str =str.toLowerCase();
	var matchStr = new Array(3);
	matchStr[0]='.gif';
	matchStr[1]='.jpg';
	for (var i=0;i<matchStr.length;i++)
	{
		if (matchStr[i] == str)
		{
		   return true;
		}
	}
	document.getElementById('up_file_span').innerHTML='.gif .jpg';
	return false;
}
//end checkImg() all

function isNotNull(str)
{ //如果str是非空字符串則返回true;
	if (typeof(str) == 'undefined') return false;
	if (typeof(str) != 'string')return false;
	if (str =='') return false;
	if (str.length < 1) return false;
	return true;
}