function CheckEmpty(Field, FieldTitle)
	{
		if (Field.value == "")
		{
			alert("请在\"" + FieldTitle + "\"中输入值.");
			Field.focus();
			return false;
		}
		
		return true;
	}
	
function CheckMinLength(Field, MinLength, FieldTitle)
	{
		if (Field.value != "")
		{
			if (Field.value.length < MinLength)
			{
				alert("\"" + FieldTitle + "\"中输入的字符请不要少于" + MinLength + "字符.");
				Field.focus();
				return false;
			}
		}
		
		return true;
	}
	
function CheckMaxLength(Field, MaxLength, FieldTitle)
	{
		if (Field.value != "")
		{
			if (Field.value.length > MaxLength)
			{
				alert("\"" + FieldTitle + "\"中输入的字符请不要超过" + MaxLength + "字符.");
				Field.focus();
				return false;
			}
		}
		
		return true;
	}
	
function CheckGifts(theForm)
{  
	if (!CheckEmpty(theForm.username, "网名"))				return false;
	if (!CheckMinLength(theForm.username, 2, "网名"))		return false;
	if (!CheckMaxLength(theForm.username, 16, "网名"))		return false;
}