IsDate()
FUNCTION: 判断一对象是否为日期，返回布尔值
SYNTAX: IsDate(expression)
ARGUMENTS: expression is any valid expression.
EXAMPLE: <%
strTest = "8/4/99"
response.write IsDate(strTest)
%>
RESULT: True
IsEmpty()
FUNCTION: 判断一对象是否初始化，返回布尔值.
SYNTAX: IsEmpty(expression)
ARGUMENTS:
EXAMPLE: <%
Dim i
response.write IsEmpty(i)
%>
RESULT: True
IsNull()
FUNCTION: 判断一对象是否为空，返回布尔值.
SYNTAX: IsNull(expression)
ARGUMENTS:
EXAMPLE: <%
Dim i
response.write IsNull(i)
%>
RESULT: False
IsNumeric()
FUNCTION: 判断一对象是否为数字，返回布尔值.
SYNTAX: IsNumeric(expression)
ARGUMENTS:
EXAMPLE: <%
i = "345"
response.write IsNumeric(i)
%>
RESULT: True
就算数字加了引号，ASP还是认为它是数字。
IsObject()
FUNCTION: 判断一对象是否为对象，返回布尔值.
SYNTAX: IsObject(expression)
ARGUMENTS:
EXAMPLE: <%
Set con = Server.CreateObject("ADODB.Connection")
response.write IsObject(con)
%>
RESULT: True
LBound()
FUNCTION: 返回指定数组维的最小可用下标.
SYNTAX: Lbound(arrayname [, dimension])
ARGUMENTS: ; dimension 指明要返回哪一维下界的整数。使用 1 表示第一维，2
表示第二维，以此类推。如果省略 dimension 参数，默认值为 1.
EXAMPLE: <%
i = Array("Monday","Tuesday","Wednesday")
response.write LBound(i)
%>
RESULT: 0
LCase()
FUNCTION: 返回字符串的小写形式
SYNTAX: Lcase(string)
ARGUMENTS: string is any valid string expression.
EXAMPLE: <%
strTest = "This is a test!"
response.write LCase(strTest)
%>
RESULT: this is a test!
Left()
FUNCTION: 返回字符串左边第length个字符以前的字符（含第length个字符).
SYNTAX: Left(string, length)
ARGUMENTS:
EXAMPLE: <%
strTest = "This is a test!"
response.write Left(strTest, 3)
%>
RESULT: Thi
