ASP中的函数应用方法及应用举例(二)-ASP教程,ASP应用

21. isobject()
  function: returns a boolean value indicating whether an expression refers to an automation object.
  syntax: isobject(expression)
  arguments: expression is any valid expression.
  example: <%
set con = server.createobject(“adodb.connection”)
response.write isobject(con)
%>
  result: true
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22. lbound()
  function: returns the base index value for a dimension of any array.
  syntax: lbound(arrayname [, dimension])
  arguments: arrayname is the name of any array; dimension is an optional number indicating the dimension
to find the lower bound.
  example: <%
i = array(“monday”,”tuesday”,”wednesday”)
response.write lbound(i)
%>
  result: 0
————————————-
  
23. lcase()
  function: returns a string that has been converted into lowercase characters.
  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!
————————————-
  
24. left()
  function: returns the number of characters from the left side of a string.
  syntax: left(string, length)
  arguments: string is any valid string expression; length is the length of characters to return.
  example: <%
strtest = “this is a test!”
response.write left(strtest, 3)
%>
  result: thi
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25. len()
  function: returns the number of characters in a string or the number of bytes required to store a
variable.
  syntax: len(string | varname)
  arguments: string is any valid string expression; varname is any valid variable name.
  example: <%
strtest = “this is a test!”
response.write len(strtest)
%>
  result: 15
(the total length of strtest is 15 characters)
26.  
ltrim()
  function: returns a string without leading spaces.
  syntax: ltrim(string)
  arguments: string is any valid string expression.
  example: <%
strtest = ” this is a test!”
response.write ltrim(strtest)
%>
  result: this is a test!
————————————-
  
27. mid()
  function: returns a specified number of characters from a string.
  syntax: mid(string, start [, length])
  arguments: string is any valid string expression; start is a numeric character position to begin
extraction from; length (optional) is the number of characters to return.
  example: <%
strtest = “this is a test! today is monday.”
response.write mid(strtest, 17, 5)
%>
  result: today
————————————-
  
28. minute()
  function: returns the number of the minutes in current system time.
  syntax: minute(time)
  arguments: time is any valid time expression.
  example: <%=minute(#12:45:32 pm#)%>
  result: 45
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29. month()
  function: returns the number of the month of the year.
  syntax: month(date)
  arguments: date is any valid date expression.
  example: <%=month(#08/04/99#)%>
  result: 8
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30. 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
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31. now()
  function: returns the current system date and time.
  syntax: now()
  arguments: none
  example: <%=now%>
  result: 8/4/99 9:30:16 am
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32. 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!
————————————-
  
33. right()
  function: returns a specified number of characters from the right side of a string.
  syntax: right(string, length)
  arguments: string is any valid string expression; length is any valid numeric expression representing
the number of characters to return.
  example: <%
strtest = “this is an test!”
response.write right(strtest, 3)
%>
  result: st!
————————————-
  
34. rnd()
  function: returns a random number.
  syntax: rnd [ (number) ]
  arguments: number is any valid numeric expression.
  example: <%
randomize()
response.write rnd()
%>
  result: any number between 0 and 1
(without randomize(), the number will not re-generate)
  
round()
  function: returns a number rounded to a specified number of decimal places.
  syntax: round(expression [, numright])
  arguments: expression is any valid numeric expression to be rounded; numright (optional) is any numeric
expression used to indicate the number of digits to the right of the decimal point.
  example: <%
i = 32.45678
response.write round(i)
%>
  result: 32
————————————-
  
35. rtrim()
  function: returns a copy of a string without trailing spaces.
  syntax: rtrim(string)
  arguments: string is any valid string expression.
  example: <%
strtest = “this is a test!! “
response.write rtrim(strtest)
%>
  result: this is a test!!
————————————-
  
36. second()
  function: returns the current seconds value of the current system time.
  syntax: second(time)
  arguments: time is any valid time expression.
  example: <%=second(#12:34:28 pm#)%>
  result: 28
————————————-
  
37. strreverse()
  function: returns a string where the character order has been reversed
  syntax:strreverse(string)
  arguments: string is any valid string expression
  example: <%
strtest = “this is a test!!”
response.write strreverse(strtest)
%>
  result: !!tset a si siht
————————————-
  
38. time()
  function: returns the current system time.
  syntax: time()
  arguments: none.
  example: <%=time%>
  result: 9:58:28 am
————————————-
  
39. trim()
  function: returns a string without leading and trailing spaces.
  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!!
————————————-
  
40. ubound()
  function: returns the largest available subscipt for a dimension of an array.
  syntax: ubound(arrayname [, dimension])
  arguments: arrayname is the name of a valid array; dimension (optional) is a number indicating the
dimension to find the upper bound.
  example: <%
i = array(“monday”,”tuesday”,”wednesday”)
response.write ubound(i)
%>
  result: 2
(array index starts with 0)
————————————-
  
41. ucase()
  function: returns a string that has been converted to uppercase characters.
  syntax: ucase(string)
  arguments: string is any valid string expression.
  example: <%
strtest = “this is a test!!”
response.write ucase(strtest)
%>
  result: this is a test!!
————————————-
  
42. vartype()
  function: returns the subtype of a variable
  syntax: vartype(varname)
  arguments: varname is the required variable name
  example: <%
i = 3
response.write vartype(i)
%>
  result: 2
(2 indicates integer. refers to asp constants)
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43. weekday()
  function: returns a whole number representing the day of the week.
  syntax: weekday(date [, firstdayofweek])
  arguments: date is any valid date expression; firstdayofweek is an optional date constant to assign the
first day of week.
  example: <%
d = #8/4/99#
response.write weekday(d)
%>
  result: 4
(4 indicates the fourth of the week, which is wednesday)
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44. weekdayname()
  function: returns the specified day of the week.
  syntax: weekdayname(weekday [, abb [, firstdayofweek]])
  arguments: weekday is the numeric representation for the day of the week; abb is an optional boolean
value (if set to true, the weekday name will be abbreviated; if set to false, the full weekday name is
displayed); and firstdayofweek is an optional date constant to assign the first day of week.
  example: <%
d = #8/4/99#
response.write weekdayname(weekday(d))
%>
  result: wednesday
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45. year()
  function: returns the current year.
  syntax: year(date)
  arguments: date is any valid date expression.
  example: <%=year(#8/4/99#)%>