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The intrinsic types Int32, Float, and String have object and interface equivalents. These are useful in the following situations:

  • An object is needed instead of a typed value (e.g. the roList object maintains a list of objects). When a function that expects a BrightScript object as a parameter is passed an integer, float, or string, BrightScript automatically creates the equivalent object.
  • If any object exposes the ifInt, ifFloat, or ifString interfaces, that object can be used in any expression that expects a typed value. For example, an roVideoEvent can be used as an integer with a value representing the event ID.


Integer Operations

If "o" is of type roInt, then these statements will have the following effects:

  • print o: Prints the value of o.GetInt()
  • i%=o: Assigns the integer i% the value of o.GetInt().
  • k=o: Presumably k is automatically typed, so it becomes another reference to the roInt o.
  • o=5: This is NOT the same as o.SetInt(5). Instead it releases o, changes the type of o to roINT32 (o is automatically typed), and assigns it to 5.

ifInt

roInt contains the ifInt interface, which provides the following:

GetInt() As Integer

Returns the integer value of the object. 

SetInt(value As Integer) As Void

Sets the integer value of the object. 

ifIntOps

roInt also contains the ifIntOps interface, which provides the following:

ToStr() As String

Returns the integer value as a string. A space is not appended to the front for positive numbers.

ifFloat

roFloat contains the ifFloat interface, which provides the following:

GetFloat() As Float

Returns the float value of the object. 

SetFloat(value As Float) As Void

Sets the float value of the object. 

ifString

roString contains the ifString interface, which provides the following:

GetString() As String

Returns the string value of the object.

SetString(value As String) As Void

Sets the string value of the object.

ifStringOps

roString also contains the ifStringOps interface, which provides the following:

Note

Some global functions offer the same functionality as ifStringOps methods. The function indexes of ifStringOps methods start at zero, while those of global functions start at one.

SetString(str As String, str_len As Integer)

Sets the string value of the object using the specified string and string-length values. This is similar to the SetSeting() method, which does not accept a parameter for string length.

AppendString(str As String, str_len As Integer)

Appends to the string value of the object using the specified string and string-length values. This method modifies itself—this can cause unexpected results when you pass an intrinsic string type, rather than a string object.

Example
x="string"
x.ifstringops.appendstring("ddd",3)
print x 'will print 'string' 
y=box("string")
y.ifstringops.appendstring("ddd",3)
print y 'will print 'stringddd'
Len() As Integer

Returns the number of characters in a string.

GetEntityEncode() As String

Returns the string with certain characters replaced with HTML entity encoding sequences:

Character
Replaced with
" (double quote)
"
' (single quote)
'
<
&lt;
>
&gt;
&
&amp;
Tokenize(delim As String) As roList

Splits a string into substrings using the specified delimiter character(s). The delim parameter can contain one or more characters to treat as delimiters. If the string object contains multiple contiguous delimiters, they will be treated as a single delimiter. This method returns the substrings as an roList object; the delimiters are not returned with the substrings.

Example
BrightScript> s = "one&&two"
BrightScript> print s.Tokenize("&")
one
two
Trim() As String

Returns the string with any leading and trailing whitespace characters (e.g. TAB, LF, CR, VT, FF, NO-BREAK SPACE) removed.

ToInt() As Integer

Returns the value of the string as an integer number.

ToFloat() As Float

Returns the value of the string as a floating point number.

Left(n As Integer) As String

Returns the first n characters of the string.

Right(n As Integer) As String

Returns the last n characters of the string.

Mid(start_index As Integer) As String

Returns a subset of the string that begins at the zero-based start_index and terminates at the end of the string.

Mid(start_index As Integer, n As Integer) As String

Returns a subset of the string, beginning at the zero-based start_index and consisting of n characters. If the string contains fewer than n characters after the specified start_index, this method will return all characters after the start_index.

Instr(substring As String) As Integer 

Returns the zero-based index of the first occurence of the substring in the string. If the substring does not occur in the string, this method returns -1. 

Instr(start_index As Integer, substring As String) As Integer

Returns the zero-based index of the first occurence of the substring after the specified start_index in the string. If the substring does not occur after the specified start_index, this method returns -1.

Tip

Instr() is also offered as a global function (note that the string index of the global function starts at 1).




Example
BrightScript> o=CreateObject("roInt")
BrightScript> o.SetInt(555)
BrightScript> print o
555
BrightScript> print o.GetInt()
555
BrightScript> print o-55
500 


An integer value of 5 is converted to type roInt automatically because the AddTail() method expects a BrightScript object as its parameter:

Example
BrightScript> list=CreateObject("roList")
BrightScript> list.AddTail(5)
BrightScript> print type(list.GetTail()) 


Here the ListDir() method returns an roList object containing roString objects:

Example
BrightScript> l=ListDir("/")
BrightScript> for i=1 to l.Count():print l.RemoveHead():next
test_movie_3.vob
test_movie_4.vob
test_movie_1.vob
test_movie_2.vob
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