function assertNotEmpty(element, title)
{
	if(element.value == "")
	{
		alert("\"" + title + "\" 内容不能为空！");
		element.focus();
		return false;
	}
	return true;
}

function assertEquals(e1, t1, e2, t2)
{
	if(e1.value != e2.value)
	{
		alert("\"" + t1 + "\" " + "与 \"" + t2 + "\" 内容不一致！");
		e2.focus();
		return false;
	}
	return true;
}

function assertMail(element, title)
{
	if(element.value.indexOf(".") == -1 ||
		element.value.indexOf("@") == -1 ||
		element.value.length < 6)
	{
		alert("\"" + title + "\" 内容必须为合法的邮件地址！");
		element.focus();
		return false;
	}
	return true;	
}

function resizeImages()
{
	window.status = "正在优化图象尺寸...";
	di = document.images;
	count1 = 0;
	count2 = 0;
	for(i = 0; i < di.length; i++)
	{
		element = di.item(i);
		if(element.className == "AutoFitImage")
		{
			count1++;
			if(resizeImage(element, 500))
				count2++;
		}
	}
	window.status = "图象尺寸优化完毕！(图象共" + di.length + "项，待优化" + count1 + "项，实际优化" + count2 + "项)";
}

function resizeImage(element, width)
{
	if(element.width > width)
	{
		oldWidth = element.width;
		oldHeight = element.height;
		element.height = element.height * width / element.width;
		element.width = width;
		element.title += "[原始尺寸:" + oldWidth + "x" + oldHeight + " 点击查看大图]";
		
		element.outerHTML = "<a href=\"" + element.src + "\" target=\"_blank\">" + element.outerHTML + "</a>";
		return true;
	}
	
	return false;
}

function getFileTitleFromFilePath(fileName)
{
	li1 = fileName.lastIndexOf('.');
	if(li1 < 0)
		li1 = fileName.length;
	
	li2 = fileName.lastIndexOf('\\') + 1;
	li3 = fileName.lastIndexOf('/') + 1;
	
	li4 = (li2 < li3 ? li3 : li2);
	
	return fileName.substring(li4, li1);
}

function onFilePathChange(filePathElement, fileTitleElement)
{
	fileTitleElement.value = getFileTitleFromFilePath(filePathElement.value);
}

function checkUploadType(e)
{
	var i = 0;
	var fileName = e.value;
	var fileName = fileName.toLowerCase();
	
	var invalidExtensions = new Array(".asp", ".aspx", ".jsp", ".pif");
	for (i = 0; i < invalidExtensions.length; i++)
	{
		if (fileName.lastIndexOf(invalidExtensions[i]) != -1)
		{
			alert("对不起！该类型的文件不能上传。");
			return false;
		}
	}
	
	return true;
}