params

-wrong parameter ("arma3dev") defined!-[[:Category:Introduced with arma3dev version 1.47|1.47]]

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Description

Description:

Parses array of params into array of private variables, similar to BIS_fnc_param. When used without argument, as shown in main syntax, internal variable _this, which is usually available inside functions and event handlers, is used as argument.
The values of passed argument array would be assigned to private variables given in the format array and respectful of their order in the array. To skip some values, give an empty string for a private variable name in format array.
To force variable value to a predefined value when argument is undefined, of a wrong type or length, use [variableName, defaultValue] format. To make sure passed value is of a specific type, supply the desired Data Types values in addition. If input is array, it is also possible to validate the length of the passed array.
If any of the processed input is undefined, of the wrong type or wrong length, default value is used instead. To log these substitutes into .rpt file, set allowFunctionsLog param in description.ext to 1.
See also: typeName

⚠

W.I.P.

Groups:

Uncategorised

Syntax

Syntax:

params [element1, element2,...elementN]

Parameters:

[element1, element2,...elementN]: Array - format array

elementN: String or Array
String is the name of a private variable (must begin with underscore _, e.g. "_myVar")
Array could be one of the following constructs:

• [variableName, defaultValue]
• [variableName, defaultValue, expectedDataTypes]
• [variableName, defaultValue, expectedDataTypes, expectedArrayLength]

variableName: String - name of a private variable (must begin with underscore _, e.g. "_myVar")
defaultValue: Anything - check if passed value is defined, if not (or nil), use this value.
expectedDataTypes: Array of direct Data Types - check if passed value is of listed Data Types. If not, use default value supplied. Empty array [] means every data type is ok.
expectedArrayLength: Number - if passed value is array, check that it is of a certain length. If not, use default value supplied.

Return Value:

Boolean - false if error occurred or default value has been used, otherwise true

Alternative Syntax

Syntax:

argument params [element1, element2,...elementN]

Parameters:

argument: Anything - A usual array of params is expected. If a non-array value is passed, it will be converted to 1 element array

[element1, element2,...elementN]: Array - format array

elementN: String or Array:
String is the name of a private variable (must begin with underscore _, e.g. "_myVar")
Array could be one of the following constructs:

• [variableName, defaultValue]
• [variableName, defaultValue, expectedDataTypes]
• [variableName, defaultValue, expectedDataTypes, expectedArrayLength]

variableName: String - name of a private variable (must begin with underscore _, e.g. "_myVar")
defaultValue: Anything - check if passed value is defined, if not (or nil), use this value.
expectedDataTypes: Array of direct Data Types - check if passed value is of listed Data Types. If not, use default value supplied. Empty array [] means every data type is ok.
expectedArrayLength: Number - if passed value is array, check that it is of a certain length. If not, use default value supplied.

Return Value:

Boolean - false if error occurred or default value has been used, otherwise true

Examples

Example 1:

[1, 2, 3] call { private ["_one", "_two", "_three"]; _one = _this select 0; _two = _this select 1; _three = _this select 2; // ..... }; // Same as above, only using params [1, 2, 3] call { params ["_one", "_two", "_three"]; // ..... };

Example 2:

[123] call { params ["_myvar"]; }; // Below would produce the same result as above 123 call { params ["_myvar"]; };

Example 3:

position player params ["", "", "_z"]; if (_z > 10) then { hint "YOU ARE FLYING!"; };

Example 4:

[1, nil, 2] params ["_var1", "_var2", "_var3"]; // All 3 variables are made private but only _var1 and _var3 are defined [1, nil, 2] params ["_var1", ["_var2", 23], "_var3"]; // All 3 variables are private and defined

Example 5:

[1, 2] call { if (!params ["_var1", "_var2", ["_var3", true, [true]]) exitWith {}; hint str [_var1, _var2, _var3]; }; // The hint shows [1,2,true] [1, 2, 3] call { if (!params ["_var1", "_var2", ["_var3", true, [true]]) exitWith {}; hint str [_var1, _var2, _var3]; }; // Error! Type Number, expected BOOL

Example 6:

[1, "ok", [1, 2, 3]] call { if (!params [ ["_var1", 0, [0]], ["_var2", "", [""]], ["_var3", [0,0,0], [[], objNull, 0], 3] ]) exitWith {}; hint "ok"; }; // Passes validation [1, 2, [3, 4, 5]] call { if (!params ["_var1", "_var2", ["_var3", [], [[], objNull, 0], 0]]) exitWith {}; hint "ok"; }; // Fails, because passed array is expected to be of 0 length, i.e. empty

Example 7:

position player params ["_x", "_y"]; player setPos [_x, _y, 100];

Example 8:

[1, 2, 3, [4, 5, 6]] call { params ["_one", "_two", "_three"]; _this select 3 params ["_four", "_five", "_six"]; };

Example 9:

{ _x params ["_group", "_index"]; // ..... } forEach waypoints group player; fn_someFnc = { params ["_position", ["_direction", 0], ["_name", ""]]; // Extract the x, y, and z from "_position" array: _position params ["_x", "_y", "_z"]; // ..... }; [position player, direction player, name player] call fn_someFnc;

Example 10:

targ addEventHandler ["HitPart", { _this select 0 params ["_target", "_shooter", "_projectile"]; }];

Additional Information

See also:

selectsetresizereverseinfindtoArraytoStringforEachcountdeleteAtdeleteRangeappendsortBIS_fnc_param

Notes

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[[Category:Introduced with arma3dev version 1.47]][[ Category: arma3dev: New Scripting Commands | PARAMS]][[ Category: arma3dev: Scripting Commands | PARAMS]]