* change simulator svg * change radio image * Remove google fonts cdn * change color of 'advanced' button * font fix * font fix 2 * display fix * change fullsceen simulator bg * Continuous servo * handle continuous state * adding shims * update rendering for continuous servos * fixing sim * fix sig * typo * fix sim * bump pxt * bump pxt * rerun travis * Input blocks revision - add Button and Pin event types - merge onPinPressed & onPinReleased in new onPinEvent function - create new onButtonEvent function * update input blocks in docs and tests * remove device_pin_release block * Hide DAL.x behind Enum * bring back deprecated blocks, but hide them * shims and locales files * fix input.input. typing * remove buildpr * bump V3 * update simulator aspect ratio * add Loudness Block * revoke loudness block * Adds soundLevel To be replaced by pxt-common-packages when DAL is updated. * Remove P0 & P3 from AnalogPin Co-authored-by: Juri <gitkraken@juriwolf.de>
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Local Variables
How to define and use local variables.
@parent language
A variable is a place where you can store and retrieve data. Variables have a name, a type, and value:
- name is how you'll refer to the variable
- type refers to the kind of data a variable can store
- value refers to what's stored in the variable
Var statement
Use the Block Editor variable statement to create a variable and the assignment operator to store something in the variable.
For example, this code stores the number 2
in the x
variable:
let x = 2;
Here's how to define a variable in the Block Editor:
-
Click
variables
. -
Change the default variable name if you like.
-
Drag a block type on the right-side of the assignment operator and click the down arrow to change the variable name.
A variable is created for the number returned by the brightness function.
let b = led.brightness();
Using variables
Once you've defined a variable, just use the variable's name whenever you need what's stored in the variable. For example, the following code shows the value stored in counter
on the LED screen:
let counter = 1;
basic.showNumber(counter);
To change the contents of a variable use the assignment operator. The following code sets counter
to 1 and then increments counter
by 10:
let counter = 1;
counter = counter + 10;
basic.showNumber(counter);
Why use variables?
If you want to remember and modify data, you'll need a variable. A counter is a great example:
let counter = 0;
input.onButtonPressed(Button.A, () => {
counter = counter + 1;
basic.showNumber(counter);
});
Local variables
Local variables exist only within the function or block of code where they're defined. For example:
// x does NOT exist here.
if (led.brightness() > 128) {
// x exists here
let x = 0;
}
Notes
- You can use the default variable names if you'd like, however, it's best to use descriptive variable names. To change a variable name in the editor, select the down arrow next to the variable and then click "new variable".