Package | Top Level |
Class | public final class String |
Inheritance | String Object |
Runtime Versions: | Flash Player 9, AIR 1.0 |
String()
function.
All the methods of the String class, except for concat()
,
fromCharCode()
, slice()
, and substr()
, are
generic, which means the methods call toString()
before performing their
operations, and you can use these methods with other non-String objects.
Because all string indexes are zero-based, the index of the last character
for any string x
is x.length - 1
.
You can call any of the methods of the String class whether you use the constructor method
new String()
to create a new string variable or simply assign a string literal value.
Unlike previous versions of ActionScript, it makes no difference whether you use the constructor,
the global function, or simply assign a string literal value. The following lines of code are equivalent:
var str:String = new String("foo"); var str:String = "foo"; var str:String = String("foo");
When setting a string variable to undefined
, Adobe® Flash® Player coerces undefined
to null
. So, the statement:
var s:String = undefined;sets the value to
null
instead of undefined
. Use the String()
function if you need to use undefined
.
See also
Property | Defined By | ||
---|---|---|---|
constructor : Object
A reference to the class object or constructor function for a given object instance. | Object | ||
length : int [read-only]
An integer specifying the number of characters in the specified String object. | String | ||
prototype : Object [static]
A reference to the prototype object of a class or function object. | Object |
Method | Defined By | ||
---|---|---|---|
Creates a new String object initialized to the specified string. | String | ||
Returns the character in the position specified by the index parameter. | String | ||
Returns the numeric Unicode character code of the character at the specified
index. | String | ||
Appends the supplied arguments to the end of the String object, converting them to strings if
necessary, and returns the resulting string. | String | ||
[static]
Returns a string comprising the characters represented by the Unicode character codes
in the parameters. | String | ||
Indicates whether an object has a specified property defined. | Object | ||
Searches the string and returns the position of the first occurrence of val
found at or after startIndex within the calling string. | String | ||
Indicates whether an instance of the Object class is in the prototype chain of the object specified
as the parameter. | Object | ||
Searches the string from right to left and returns the index of the last occurrence
of val found before startIndex. | String | ||
Compares the sort order of two or more strings and returns the result of the comparison as an integer. | String | ||
Matches the specifed pattern against the
string. | String | ||
Indicates whether the specified property exists and is enumerable. | Object | ||
Matches the specifed pattern against the string and returns a new string
in which the first match of pattern is replaced with the content specified by repl. | String | ||
Searches for the specifed pattern and returns the index of
the first matching substring. | String | ||
Sets the availability of a dynamic property for loop operations. | Object | ||
Returns a string that includes the startIndex character
and all characters up to, but not including, the endIndex character. | String | ||
Splits a String object into an array of substrings
by dividing it wherever the specified delimiter parameter
occurs. | String | ||
Returns a substring consisting of the characters that start at the specified
startIndex and with a length specified by len. | String | ||
Returns a string consisting of the character specified by startIndex
and all characters up to endIndex - 1. | String | ||
Returns a copy of this string, with all uppercase characters converted
to lowercase. | String | ||
Returns the string representation of this object, formatted according to locale-specific conventions. | Object | ||
Returns a copy of this string, with all lowercase characters converted
to uppercase. | String | ||
Returns a copy of this string, with all uppercase characters converted
to lowercase. | String | ||
Returns the string representation of the specified object. | Object | ||
Returns a copy of this string, with all lowercase characters converted
to uppercase. | String | ||
Returns the primitive value of a String instance. | String |
length | property |
length:int
[read-only] Runtime Versions: | Flash Player 9, AIR 1.0 |
An integer specifying the number of characters in the specified String object.
Because all string indexes are zero-based, the index of the last character for any
string x
is x.length - 1
.
Implementation
public function get length():int
String | () | Constructor |
public function String(val:String)
Runtime Versions: | Flash Player 9, AIR 1.0 |
Creates a new String object initialized to the specified string.
Note: Because string literals use less overhead than String objects and are generally easier to use, you should use string literals instead of the String class unless you have a good reason to use a String object rather than a string literal.
Parametersval:String — The initial value of the new String object.
|
charAt | () | method |
AS3 function charAt(index:Number = 0):String
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns the character in the position specified by the index
parameter.
If index
is not a number from 0 to string.length - 1
, an
empty string is returned.
This method is similar to String.charCodeAt()
except that the returned
value is a character, not a 16-bit integer character code.
Parameters
index:Number (default = 0 ) — An integer specifying the position of a character in the string. The first
character is indicated by 0 , and the last character is indicated by
my_str.length - 1 .
|
String — The character at the specified index. Or an empty string if the
specified index is outside the range of this string's indices.
|
See also
charCodeAt | () | method |
AS3 function charCodeAt(index:Number = 0):Number
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns the numeric Unicode character code of the character at the specified
index
. If index
is not a number from 0 to
string.length - 1
, NaN
is returned.
This method is similar to String.charAt()
except that the returned
value is a 16-bit integer character code, not the actual character.
Parameters
index:Number (default = 0 ) — An integer that specifies the position of a character in the string. The
first character is indicated by 0, and the last character is indicated by
my_str.length - 1 .
|
Number — The Unicode character code of the character at the specified index. Or
NaN if the index is outside the range of this string's indices.
Unicode values are defined in the Unicode Character Database specification. |
See also
concat | () | method |
AS3 function concat(... args):String
Runtime Versions: | Flash Player 9, AIR 1.0 |
Appends the supplied arguments to the end of the String object, converting them to strings if necessary, and returns the resulting string. The original value of the source String object remains unchanged.
Parameters
... args — Zero or more values to be concatenated.
|
String — A new string consisting of this string concatenated
with the specified parameters.
|
fromCharCode | () | method |
AS3 static function fromCharCode(... charCodes):String
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns a string comprising the characters represented by the Unicode character codes in the parameters.
Parameters
... charCodes — A series of decimal integers that represent Unicode values.
Unicode values are defined in the Unicode Character Database specification. |
String — The string value of the specified Unicode character codes.
|
indexOf | () | method |
AS3 function indexOf(val:String, startIndex:Number = 0):int
Runtime Versions: | Flash Player 9, AIR 1.0 |
Searches the string and returns the position of the first occurrence of val
found at or after startIndex
within the calling string. This index is zero-based,
meaning that the first character in a string is considered to be at index 0--not index 1. If
val
is not found, the method returns -1.
Parameters
val:String — The substring for which to search.
| |
startIndex:Number (default = 0 ) — An optional integer specifying the starting index of the search.
|
int — The index of the first occurrence of the specified substring or -1 .
|
See also
lastIndexOf | () | method |
AS3 function lastIndexOf(val:String, startIndex:Number = 0x7FFFFFFF):int
Runtime Versions: | Flash Player 9, AIR 1.0 |
Searches the string from right to left and returns the index of the last occurrence
of val
found before startIndex
. The index is zero-based,
meaning that the first character is at index 0, and the last is at string.length
- 1
. If val
is not found, the method returns -1
.
Parameters
val:String — The string for which to search.
| |
startIndex:Number (default = 0x7FFFFFFF ) — An optional integer specifying the starting index from which to
search for val . The default is the maximum value allowed for an index.
If startIndex is not specified, the search starts at the last item in the string.
|
int — The position of the last occurrence of the specified substring or -1 if not found.
|
See also
localeCompare | () | method |
AS3 function localeCompare(other:String, ... values):int
Runtime Versions: | AIR 1.0, Flash Player 9 |
Compares the sort order of two or more strings and returns the result of the comparison as an integer. While this
method is intended to handle the comparison in a locale-specific way, the ActionScript 3.0 implementation
does not produce a different result from other string comparisons such as the equality (==
) or
inequality (!=
) operators.
If the strings are equivalent, the return value is 0.
If the original string value precedes the string value specified by other
,
the return value is a negative integer, the absolute value of which represents
the number of characters that separates the two string values.
If the original string value comes after other
,
the return value is a positive integer, the absolute value of which represents
the number of characters that separates the two string values.
Parameters
other:String — A string value to compare.
| |
... values — Optional set of more strings to compare.
|
int — The value 0 if the strings are equal. Otherwise, a negative integer if the original
string precedes the string argument and a positive integer if the string argument precedes
the original string. In both cases the absolute value of the number represents the difference
between the two strings.
|
match | () | method |
AS3 function match(pattern:*):Array
Runtime Versions: | AIR 1.0, Flash Player 9 |
Matches the specifed pattern
against the
string.
Parameters
pattern:* — The pattern to match, which can be any type of object, but it is typically
either a string or a regular expression. If the pattern is not a regular expression
or a string, then the method converts it to a string before executing.
|
Array — An array of strings consisting of all substrings in
the string that match the specified pattern .
If
If no match is found, the method returns |
See also
replace | () | method |
AS3 function replace(pattern:*, repl:Object):String
Runtime Versions: | AIR 1.0, Flash Player 9 |
Matches the specifed pattern
against the string and returns a new string
in which the first match of pattern
is replaced with the content specified by repl
.
The pattern
parameter can be a string or a regular expression. The repl
parameter
can be a string or a function; if it is a function, the string returned
by the function is inserted in place of the match. The original string is not modified.
In the following example, only the first instance of "sh" (case-sensitive) is replaced:
var myPattern:RegExp = /sh/; var str:String = "She sells seashells by the seashore."; trace(str.replace(myPattern, "sch")); // She sells seaschells by the seashore.
In the following example, all instances of "sh" (case-sensitive)
are replaced because the g
(global) flag is set in the regular expression:
var myPattern:RegExp = /sh/g; var str:String = "She sells seashells by the seashore."; trace(str.replace(myPattern, "sch")); // She sells seaschells by the seaschore.
In the following example, all instance of "sh"
are replaced because the g
(global) flag is set in the regular expression
and the matches are not case-sensitive because the i
(ignoreCase) flag is set:
var myPattern:RegExp = /sh/gi; var str:String = "She sells seashells by the seashore."; trace(str.replace(myPattern, "sch")); // sche sells seaschells by the seaschore.
Parameters
pattern:* — The pattern to match, which can be any type of object, but it is typically
either a string or a regular expression. If you specify a pattern parameter
that is any object other than a string or a regular expression, the toString() method is
applied to the parameter and the replace() method executes using the resulting string
as the pattern .
| |||||||||||||||
repl:Object — Typically, the string that is inserted in place of the matching content. However, you can
also specify a function as this parameter. If you specify a function, the string returned
by the function is inserted in place of the matching content.
When you specify a string as the
For example, the following shows the use of the var str:String = "flip-flop"; var pattern:RegExp = /(\w+)-(\w+)/g; trace(str.replace(pattern, "$2-$1")); // flop-flip When you specify a function as the
For example, consider the following: var str1:String = "abc12 def34"; var pattern:RegExp = /([a-z]+)([0-9]+)/; var str2:String = str1.replace(pattern, replFN); trace (str2); // 12abc 34def function replFN():String { return arguments[2] + arguments[1]; } The call to the {"abc12", "abc", "12", 0, "abc12 def34"} The second time, the pattern matches the substring {"def34", "def", "34", 6, "abc123 def34"} |
String — The resulting string. Note that the source string remains unchanged.
|
See also
search | () | method |
AS3 function search(pattern:*):int
Runtime Versions: | AIR 1.0, Flash Player 9 |
Searches for the specifed pattern
and returns the index of
the first matching substring. If there is no matching substring, the method returns
-1
.
Parameters
pattern:* — The pattern to match, which can be any type of object but is typically
either a string or a regular expression.. If the pattern is not a regular expression
or a string, then the method converts it to a string before executing.
Note that if you specify a regular expression, the method ignores the global flag ("g") of the
regular expression, and it ignores the lastIndex property of the regular
expression (and leaves it unmodified). If you pass an undefined value (or no value),
the method returns -1 .
|
int — The index of the first matching substring, or -1 if
there is no match. Note that the string is zero-indexed; the first character of
the string is at index 0, the last is at string.length - 1 .
|
See also
slice | () | method |
AS3 function slice(startIndex:Number = 0, endIndex:Number = 0x7fffffff):String
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns a string that includes the startIndex
character
and all characters up to, but not including, the endIndex
character. The original String object is not modified.
If the endIndex
parameter is not specified, then the end of the
substring is the end of the string. If the character indexed by startIndex
is the same as or to the right of the
character indexed by endIndex
, the method returns an empty string.
Parameters
startIndex:Number (default = 0 ) — The zero-based index of the starting point for the slice. If
startIndex is a negative number, the slice is created from right-to-left, where
-1 is the last character.
| |
endIndex:Number (default = 0x7fffffff ) — An integer that is one greater than the index of the ending point for
the slice. The character indexed by the endIndex parameter is not included in the extracted
string.
If endIndex is a negative number, the ending point is determined by
counting back from the end of the string, where -1 is the last character.
The default is the maximum value allowed for an index. If this parameter is omitted, String.length is used.
|
String — A substring based on the specified indices.
|
See also
split | () | method |
AS3 function split(delimiter:*, limit:Number = 0x7fffffff):Array
Runtime Versions: | Flash Player 9, AIR 1.0 |
Splits a String object into an array of substrings
by dividing it wherever the specified delimiter
parameter
occurs.
If the delimiter
parameter is a regular expression, only
the first match at a given position of the string is considered,
even if backtracking could find a nonempty substring match at that
position. For example:
var str:String = "ab"; var results:Array = str.split(/a*?/); // results == ["","b"] results = str.split(/a*/); // results == ["","b"].)
If the delimiter
parameter is a regular expression
containing grouping parentheses, then each time the
delimiter
is matched, the results (including any
undefined results) of the grouping parentheses are spliced into the
output array. For example
var str:String = "Thi5 is a tricky-66 example."; var re:RegExp = /(\d+)/; var results:Array = str.split(re); // results == ["Thi","5"," is a tricky-","66"," example."]
If the limit
parameter is specified, then
the returned array will have no more than the specified
number of elements.
If the delimiter
is an empty string, an empty
regular expression, or a regular expression that can match an empty
string, each single character in the string
is output as an element in the array.
If the delimiter
parameter is undefined, the entire
string is placed into the first element of the returned
array.
Parameters
delimiter:* — The pattern that specifies where to split this string. This can be any type of
object but is typically either a string or a regular expression. If the delimiter
is not a regular expression or string, then the method converts it to a string before executing.
| |
limit:Number (default = 0x7fffffff ) — The maximum number of items to place into the array.
The default is the maximum value allowed.
|
Array — An array of substrings.
|
See also
substr | () | method |
AS3 function substr(startIndex:Number = 0, len:Number = 0x7fffffff):String
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns a substring consisting of the characters that start at the specified
startIndex
and with a length specified by len
. The original
string is unmodified.
Parameters
startIndex:Number (default = 0 ) — An integer that specified the index of the first character to be
used to create the substring. If startIndex is a negative number, the
starting index is determined from the end of the string, where -1 is the
last character.
| |
len:Number (default = 0x7fffffff ) — The number of characters in the substring being created.
The default value is the maximum value allowed. If len
is not specified, the substring includes all the characters from startIndex
to the end of the string.
|
String — A substring based on the specified parameters.
|
substring | () | method |
AS3 function substring(startIndex:Number = 0, endIndex:Number = 0x7fffffff):String
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns a string consisting of the character specified by startIndex
and all characters up to endIndex - 1
. If endIndex
is not
specified, String.length
is used. If the value of startIndex
equals the value of endIndex
, the method returns an empty string.
If the value of startIndex
is greater than the value of
endIndex
, the parameters are automatically swapped before the function
executes. The original string is unmodified.
Parameters
startIndex:Number (default = 0 ) — An integer specifying the index of the first character used to create
the substring. Valid values for startIndex are 0 through
String.length . If startIndex is a negative value, 0
is used.
| |
endIndex:Number (default = 0x7fffffff ) — An integer that is one greater than the index of the last character in the
extracted substring. Valid values for endIndex are 0 through
String.length . The character at endIndex is not included in
the substring. The default is the maximum value allowed for an index.
If this parameter is omitted, String.length is used. If
this parameter is a negative value, 0 is used.
|
String — A substring based on the specified parameters.
|
toLocaleLowerCase | () | method |
AS3 function toLocaleLowerCase():String
Runtime Versions: | AIR 1.0, Flash Player 9 |
Returns a copy of this string, with all uppercase characters converted
to lowercase. The original string is unmodified. While this
method is intended to handle the conversion in a locale-specific way, the ActionScript 3.0 implementation
does not produce a different result from the toLowerCase()
method.
String — A copy of this string with all uppercase characters converted
to lowercase.
|
See also
toLocaleUpperCase | () | method |
AS3 function toLocaleUpperCase():String
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns a copy of this string, with all lowercase characters converted
to uppercase. The original string is unmodified. While this
method is intended to handle the conversion in a locale-specific way, the ActionScript 3.0 implementation
does not produce a different result from the toUpperCase()
method.
String — A copy of this string with all lowercase characters converted
to uppercase.
|
See also
toLowerCase | () | method |
AS3 function toLowerCase():String
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns a copy of this string, with all uppercase characters converted to lowercase. The original string is unmodified.
This method converts all characters (not simply A-Z) for which Unicode lowercase equivalents exist:
var str:String = " JOSÉ BARÇA"; trace(str.toLowerCase()); // josé barça
These case mappings are defined in the Unicode Character Database specification.
ReturnsString — A copy of this string with all uppercase characters converted
to lowercase.
|
See also
toUpperCase | () | method |
AS3 function toUpperCase():String
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns a copy of this string, with all lowercase characters converted to uppercase. The original string is unmodified.
This method converts all characters (not simply a-z) for which Unicode uppercase equivalents exist:
var str:String = "José Barça"; trace(str.toUpperCase()); // JOSÉ BARÇA
These case mappings are defined in the Unicode Character Database specification.
ReturnsString — A copy of this string with all lowercase characters converted
to uppercase.
|
See also
valueOf | () | method |
AS3 function valueOf():String
Language Version: | ActionScript 3.0 |
Runtime Versions: | Flash Player 9, AIR 1.0 |
Returns the primitive value of a String instance. This method is designed to
convert a String object into a primitive string value. Because Flash Player
automatically calls valueOf()
when necessary,
you rarely need to explicitly call this method.
String — The value of the string.
|
- The constructor for StringExample declares several local String instances, which are initialized with various strings and a new StringHelper object.
- The StringHelper class has the following methods:
replace()
: calls thesplit()
andjoin()
methods of String to remove a substring of the string passed in with a new one.trim()
: calls bothtrimBack()
andtrimFront()
using the strings passed in and returns the updated string.trimFront()
:recursively removes all characters that match thechar
parameter, starting from the front of the string and working toward the end, until the first character in the string does not matchchar
and returns the updated string.trimBack()
: recursively removes all characters that match thechar
parameter, starting from the end of the string and working backward, until the last character in the string does not matchchar
and returns the updated string.stringToCharacter()
: returns the first character of the string passed to it.
- Three strings are then produced using the declared string variables with a call to the
replace()
method used to produce the second string andtrim()
to produce the third string.
package { import flash.display.Sprite; public class StringExample extends Sprite { public function StringExample() { var companyStr:String = new String(" Company X"); var productStr:String = "Product Z Basic "; var emptyStr:String = " "; var strHelper:StringHelper = new StringHelper(); var companyProductStr:String = companyStr + emptyStr + productStr; trace("'" + companyProductStr + "'"); // ' Company X Product Z Basic ' companyProductStr = strHelper.replace(companyProductStr, "Basic", "Professional"); trace("'" + companyProductStr + "'"); // ' Company X Product Z Professional ' companyProductStr = strHelper.trim(companyProductStr, emptyStr); trace("'" + companyProductStr + "'"); // 'Company X Product Z Professional' } } } class StringHelper { public function StringHelper() { } public function replace(str:String, oldSubStr:String, newSubStr:String):String { return str.split(oldSubStr).join(newSubStr); } public function trim(str:String, char:String):String { return trimBack(trimFront(str, char), char); } public function trimFront(str:String, char:String):String { char = stringToCharacter(char); if (str.charAt(0) == char) { str = trimFront(str.substring(1), char); } return str; } public function trimBack(str:String, char:String):String { char = stringToCharacter(char); if (str.charAt(str.length - 1) == char) { str = trimBack(str.substring(0, str.length - 1), char); } return str; } public function stringToCharacter(str:String):String { if (str.length == 1) { return str; } return str.slice(0, 1); } }
Fri Mar 19 2010, 02:45 AM -07:00