ASP中的函数应用方法及应用举例(一)

1.array()
  function: returns a variant containing an array.
  syntax: array(list)
  arguments: list is a comma-delimited list of values to add to the array.
  example: <%
dim myarray()
for i = 1 to 7
   redim preserve myarray(i)
   myarray(i) = weekdayname(i)
next
%>
  result: creates an array contains 7 elements:
myarray("sunday","monday", ... ... "saturday")
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2. cint()
  function: returns an expression that has been converted to an interget subtype.
  syntax: cint(expression)
  arguments: expression is any valid expression
  example: <%
f = "234"
response.write cint(f) + 2
%>
  result: 236
converts string "234" to mathematic value 234.
if f is empty (un-initialized variable), cint() returns 0.
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3. createobject()
  function: creates and returns a reference to activex automation object.
  syntax: createobject(objname)
  arguments: objname is any valid activex automation object.
  example: <%
set con = server.createobject("adodb.connection")
%>
  result:  
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4. cstr()
  function: returns an expression that has been converted to a variant of subtype string.
  syntax: cstr(expression)
  arguments: expression is any valid expression
  example: <%
s = 3 + 2
response.write "the result is: " & cstr(s)
%>
  result: converts a mathematic value 5 to a string "5".
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5. date()
  function: returns the current system date.
  syntax: date()
  arguments: none.
  example: <%=date%>
  result: 8/4/99
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6. dateadd()
  function: returns a date to which a specific time interval has been added.
  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";
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7. datediff()
  function: returns the number of intervals between two dates.
  syntax: datediff(timeinterval,date1,date2 [, firstdayofweek [, firstweekofyear]])
  arguments: timeinterval is the time interval to add; date is a valid date expression; firstdayofweek and