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asp常用函数
array()
function: 返回一个数组
syntax: array(list)
arguments: 字符，数字均可
example: <%
dim myarray()
for i = 1 to 7
redim preserve myarray(i)
myarray(i) = weekdayname(i)
next
%>
result: 建立了一个包含7个元素的数组myarray
myarray("sunday","monday", … … "saturday")
cint()
function: 将一个表达式转化为数字类型
syntax: cint(expression)
arguments: 任何有效的字符均可
example: <%
f = "234"
response.write cint(f) + 2
%>
result: 236
转化字符"234"为数字"234"，如果字符串为空，则返回0值
createobject()
function: 建立和返回一个已注册的activex组件的实例。
syntax: createobject(objname)
arguments: objname 是任何一个有效、已注册的activex组件的名字.
example: <%
set con = server.createobject("adodb.connection")
%>
result:
cstr()
function: 转化一个表达式为字符串.
syntax: cstr(expression)
arguments: expression 是任何有效的表达式。
example: <%
s = 3 + 2
response.write "the result is: " & cstr(s)
%>
result: 转化数字“5”为字符“5”。
date()
function: 返回当前系统日期.
syntax: date()
arguments: none.
example: <%=date%>
result: 8/4/99
dateadd()
function: 返回一个被改变了的日期。
syntax: dateadd(timeinterval,number,date)
arguments: timeinterval is the time interval to add; number is amount of
time intervals to add; and date is the starting date.
example: <%
currentdate = #8/4/99#
newdate = dateadd("m",3,currentdate)
response.write newdate
%>
<%
currentdate = #12:34:45 pm#
newdate = dateadd("h",3,currentdate)
response.write newdate
%>
result: 11/4/99
3:34:45 pm
"m" = "month";
"d" = "day";
if currentdate is in time format then,
"h" = "hour";
"s" = "second";
datediff()
function: 返回两个日期之间的差值 。
syntax: datediff(timeinterval,date1,date2 [, firstdayofweek ][,
firstweekofyear]])
arguments: timeinterval 表示相隔时间的类型，如“m“表示“月”。
example: <%
fromdate = #8/4/99#
todate = #1/1/2000#
response.write "there are " & _
datediff("d",fromdate,todate) & _
" days to millenium from 8/4/99."
%>
result: 从8/4/99 到2000年还有 150 天.
day()
function: 返回一个月的第几日 .
syntax: day(date)
arguments: date 是任何有效的日期。
example: <%=day(#8/4/99#)%>
result: 4
formatcurrency()
function: 返回表达式，此表达式已被格式化为货币值
syntax: formatcurrency(expression [, digit ][, leadingdigit ][, paren ][,
groupdigit]]]])
arguments: digit 指示小数点右侧显示位数的数值。默认值为 -1，指示使用的是
计算机的区域设置; leadingdigit 三态常数，指示是否显示小数值小数点前面的
零。
example: <%=formatcurrency(34.3456)%>
result: $34.35
formatdatetime()
function: 返回表达式，此表达式已被格式化为日期或时间
syntax: formatdatetime(date, [, namedformat])
arguments: namedformat 指示所使用的日期/时间格式的数值，如果省略，则使用
vbgeneraldate.
example: <%=formatdatetime("08/4/99", vblongdate)%>
result: wednesday, august 04, 1999
formatnumber()
function: 返回表达式，此表达式已被格式化为数值.
syntax: formatnumber(expression [, digit ][, leadingdigit ][, paren ][,
groupdigit]]]])
arguments: digit 指示小数点右侧显示位数的数值。默认值为 -1，指示使用的是
计算机的区域设置。; leadingdigit i指示小数点右侧显示位数的数值。默认值为 –
1，指示使用的是计算机的区域设置。; paren 指示小数点右侧显示位数的数值。默认
值为 -1，指示使用的是计算机的区域设置。; groupdigit i指示小数点右侧显示位数
的数值。默认值为 -1，指示使用的是计算机的区域设置。.
example: <%=formatnumber(45.324567, 3)%>
result: 45.325
formatpercent()
function: 返回表达式，此表达式已被格式化为尾随有 % 符号的百分比（乘以
100 ）。 (%)
syntax: formatpercent(expression [, digit ][, leadingdigit ][, paren ][,
groupdigit]]]])
arguments: 同上.
example: <%=formatpercent(0.45267, 3)%>
result: 45.267%
hour()
function: 以24时返回小时数.
syntax: hour(time)
arguments:
example: <%=hour(#4:45:34 pm#)%>
result: 16
(hour has been converted to 24-hour system)
instr()
function: 返回字符或字符串在另一个字符串中第一次出现的位置.
syntax: instr([start, ] strtobesearched, strsearchfor [, compare])
arguments: start为搜索的起始值，strtobesearched接受搜索的字符串
strsearchfor要搜索的字符.compare比较方式（详细见asp常数）
example: <%
strtext = "this is a test!!"
pos = instr(strtext, "a")
response.write pos
%>
result: 9
instrrev()
function: 同上，只是从字符串的最后一个搜索起
syntax: instrrev([start, ] strtobesearched, strsearchfor [, compare])
arguments: 同上.
example: <%
strtext = "this is a test!!"
pos = instrrev(strtext, "s")
response.write pos
%>
result: 13
int()
function: 返回数值类型,不四舍五入，注意取值是不大于它的整数。
syntax: int(number)
arguments:
example: <%=int(32.89)%> <%=int(-3.33)%>
result: 32 -4
isarray()
function: 判断一对象是否为数组，返回布尔值 .
syntax: isarray(name)
arguments:
example: <%
strtest = "test!"
response.write isarray(strtest)
%>
result: false
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
len()
function: 返回字符串的长度.
syntax: len(string | varname)
arguments:
example: <%
strtest = "this is a test!"
response.write len(strtest)
%>
result: 15
ltrim()
function: 去掉字符串左边的空格.
syntax: ltrim(string)
arguments:
example: <%
strtest = " this is a test!"
response.write ltrim(strtest)
%>
result: this is a test!
mid()
function: 返回特定长度的字符串(从start开始,长度为length).
syntax: mid(string, start [, length])
arguments:
example: <%
strtest = "this is a test! today is monday."
response.write mid(strtest, 17, 5)
%>
result: today
minute()
function: 返回时间的分钏.
syntax: minute(time)
arguments:
example: <%=minute(#12:45:32 pm#)%>
result: 45
month()
function: 返回日期.
syntax: month(date)
arguments: date is any valid date expression.
example: <%=month(#08/04/99#)%>
result: 8
monthname()
function: returns a string identifying the specified month.
syntax: monthname(month, [, abb])
arguments: month is the numeric representation for a given month; abb
(optional) is a boolean value used to display month abbreviation. true
will display the abbreviated month name and false (default) will not show
the abbreviation.
example: <%=monthname(month(#08/04/99#))%>
result: august
now()
function: returns the current system date and time.
syntax: now()
arguments: none
example: <%=now%>
result: 8/4/99 9:30:16 am
replace()
function: returns a string in which a specified sub-string has been
replaced with another substring a specified number of times.
syntax: replace(strtobesearched, strsearchfor, strreplacewith [, start
][, count ][, compare]]])
arguments: strtobesearched is a string expression containing a sub-
string to be replaced; strsearchfor is the string expression to search for
within strtobesearched; strreplacewith is the string expression to replace
sub-string strsearchfor; start (optional) is the numeric character
position to begin search; count (optional) is a value indicating the
comparision constant.
example: <%
strtest = "this is an apple!"
response.write replace(strtest, "apple", "orange")
%>
result: this is an orange!
right()
function: 返回字符串右边第length个字符以前的字符（含第length个字符).
syntax: right(string, length)
arguments: .
example: <%
strtest = "this is an test!"
response.write right(strtest, 3)
%>
result: st!
rnd()
function: 产生一个随机数.
syntax: rnd [ (number) ]
arguments:
example: <%
randomize()
response.write rnd()
%>
result: 任何一个在0 到 1 之间的数
round()
function: 返回按指定位数进行四舍五入的数值.
syntax: round(expression [, numright])
arguments: numright数字表明小数点右边有多少位进行四舍五入。如果省略，则
round 函数返回整数.
example: <%
i = 32.45678
response.write round(i)
%>
result: 32
rtrim()
function: 去掉字符串右边的字符串.
syntax: rtrim(string)
arguments:
example: <%
strtest = "this is a test!! "
response.write rtrim(strtest)
%>
result: this is a test!!
second()
function: 返回秒.
syntax: second(time)
arguments: .
example: <%=second(#12:34:28 pm#)%>
result: 28
strreverse()
function: 反排一字符串
syntax: strreverse(string)
arguments:
example: <%
strtest = "this is a test!!"
response.write strreverse(strtest)
%>
result: !!tset a si siht
time()
function: 返回系统时间.
syntax: time()
arguments: .
example: <%=time%>
result: 9:58:28 am
trim()
function: 去掉字符串左右的空格.
syntax: trim(string)
arguments: string is any valid string expression.
example: <%
strtest = " this is a test!! "
response.write trim(strtest)
%>
result: this is a test!!
ubound()
function: 返回指定数组维数的最大可用下标.
syntax: ubound(arrayname [, dimension])
arguments: ; dimension (optional) 指定返回哪一维上界的整数。1 表示第一
维，2 表示第二维，以此类推。如果省略 dimension 参数，则默认值为 1.
example: <%
i = array("monday","tuesday","wednesday")
response.write ubound(i)
%>
result: 2
ucase()
function: 返回字符串的大写形式.
syntax: ucase(string)
arguments:
example: <%
strtest = "this is a test!!"
response.write ucase(strtest)
%>
result: this is a test!!
vartype()
function: 返回指示变量子类型的值
syntax: vartype(varname)
arguments:
example: <%
i = 3
response.write vartype(i)
%>
result: 2(数字)详见"asp常数"
weekday()
function: 返回在一周的第几天.
syntax: weekday(date [, firstdayofweek])
arguments: .
example: <%
d = #8/4/99#
response.write weekday(d)
%>
result: 4(星期三)
weekdayname()
function: 返回一周第几天的名字.
syntax: weekdayname(weekday [, abb ][, firstdayofweek]])
arguments: abb可选。boolean 值，指明是否缩写表示星期各天的名称。如果省
略， 默认值为 false，即不缩写星期各天的名称.firstdayofweek指明星期第一天的
数值
example: <%
d = #8/4/99#
response.write weekdayname(weekday(d))
%>
result: wednesday
year()
function: 返回当前的年份.
syntax: year(date)
arguments:
example: <%=year(#8/4/99#)%>
result: 1999
