61 lines
2.0 KiB
Markdown
61 lines
2.0 KiB
Markdown
# String
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a piece of text.
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### @parent js/language
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A *String* is a sequence of characters. For the BBC micro:bit, ASCII character codes 32 to 126 are supported; letters, digits, punctuation marks, and a few symbols. All other character codes appear as a ? on the [LED screen](/device/screen).
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### Declare a string
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Use the [var statement](/reference/variables/var) and the [assignment operator](/reference/variables/assign) `:=` to declare a new *local* string variable. Like this:
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```
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let str = "this is a string"
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```
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To declare a string using the [Touch Develop editor](/js/editor):
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1. Click `var` (on the Code Keyboard).
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2. Type a name for your new string variable.
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2. Click on the right side of the `:=` operator.
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3. Type `"` (or click `"abc"`) and then type a string like `hello`.
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4. Click the check mark.
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Your code should look something like this:
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```
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let salutation = "Hello"
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```
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### The function `show string`
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Use [show string](/reference/basic/show-string) to display a string on the [LED screen](/device/screen). If the string is multiple characters, the string scrolls right to left. The following example displays `Hello world!` on the micro:bit screen:
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```
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basic.showString("Hello world!", 100)
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```
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The first parameter of `show string` specifies the string, and the second parameter specifies the number of milliseconds between scrolling by one LED column - the larger the value, the slower the scroll will be.
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### More string functions
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Want to compare or concatenate strings? Check out the [string functions](/reference/types/string-functions).
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### Global string variables
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Unlike [local variables](/reference/variables/var), global variables are accessible across functions and in nested code blocks. To find out how to declare a global string variable, see [global variables](/js/data).
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### Lessons
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[letter up](/lessons/letter-up)
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### See also
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[local variables](/reference/variables/var), [global variables](/js/data), [string functions](/reference/types/string-functions), [Number](/reference/types/number), [show string](/reference/basic/show-string)
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