Difference between revisions of "Category:LSL String"

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(mention surprises of ("\t" != llUnescapeURL("%0A")) && ("\r" != llUnescapeURL("%0D")))
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The result: only strings that are inside your script when it is compiled will get, say, \n turned into a "new line" character.  Text you read in from a notecard, chat, http, etc, will not be checked for escape codes -- that same \n typed in a notecard doesn't automatically turn into a "new line" character in any case.  You'll have to do that yourself, if you really really need it for some reason.
The result: only strings that are inside your script when it is compiled will get, say, \n turned into a "new line" character.  Text you read in from a notecard, chat, http, etc, will not be checked for escape codes -- that same \n typed in a notecard doesn't automatically turn into a "new line" character in any case.  You'll have to do that yourself, if you really really need it for some reason.


Note: People who know come to LSL from C and Java and such languages may find these LSL string escape rules confusing while new. LSL "\n" means llUnescapeURL("%0A"), same as C and Java, but "\t" means llUnescapeURL("%20%20%20%20") rather than llUnescapeURL("%09"), and "\r" means "r" rather than llUnescapeURL("%0D"), etc.


{{#vardefine:p_name_desc|variable name
{{#vardefine:p_name_desc|variable name

Revision as of 06:09, 8 September 2007

A string is text data. The length of a string is only limited by available script memory. String values are enclosed in double quotes when defined in LSL text. Any character may be used in a string though some will need to be escaped.

Strings can be concatenated using the + operator.

Escape codes
Substring Replaced with
\t four spaces
\n new line
\" double quote
\\ backslash

String examples:

"Hello Avatar!"
"Yes"
"No"
"It's 10 o'clock."
"I am 21 years old!"
"Help " + "me"
EOF
//The following two strings have the same value.
"I scream,\nyou scream,\nwe all scream,\nfor ice-cream!"
"I scream,
you scream,
we all scream,
for ice-cream!"

Note: escape codes (listed above) are translated when the script is compiled, and not while it's running. The result: only strings that are inside your script when it is compiled will get, say, \n turned into a "new line" character. Text you read in from a notecard, chat, http, etc, will not be checked for escape codes -- that same \n typed in a notecard doesn't automatically turn into a "new line" character in any case. You'll have to do that yourself, if you really really need it for some reason.

Note: People who know come to LSL from C and Java and such languages may find these LSL string escape rules confusing while new. LSL "\n" means llUnescapeURL("%0A"), same as C and Java, but "\t" means llUnescapeURL("%20%20%20%20") rather than llUnescapeURL("%09"), and "\r" means "r" rather than llUnescapeURL("%0D"), etc.


Variable: string name;

string name;

Declares a variable of type string named name, with the value ""

• variable name variable name

Variable: string name = value;

string name = value;

Declares a variable of type string named name, with the value value.

• variable name variable name
• expression value string expression or constant

Typecast: (string)value

(string)value

Converts value to a value of type string.

• expression value expression or constant

Operators

See Operators for more information.

Combine: value1 + value2

(value1 + value2)

Combines two strings into a single string without modifying the inputs. Appends value2 to value1 and returns the resulting string.

• expression value1 string expression or constant
• expression value2 string expression or constant

Comparison: value1 == value2

(value1 == value2)

Compares two strings, returns one if same length and same characters, else returns zero. This operator works exactly like !strcmp(value1, value2) in C, thus technically differs from the counterintuitive behavior of the == operator in C and in Java.

• expression value1 string expression or constant
• expression value2 string expression or constant

Comparison: value1 != value2

(value1 == value2)

Compares two strings, returns zero if same length and same characters, otherwise non-zero. This operator works exactly like strcmp(value1, value2) in C, thus technically differs from the counterintuitive behavior of the != operator in C and in Java.

• expression value1 string expression or constant
• expression value2 string expression or constant

Examples

integer int = 48934;
string str = (string)int;
string str_2;
str_2 = str;

Useful Functions

String functions in the CombinedLibrary

•  str_replace replace all instances of a string with another string in a target string.
•  TrimRight Trim characters from the right end of a string
•  TrimLeft Trim characters from the left end of a string
•  TrimBoth Trim characters from the both ends of a string