upperCase()

upperCase(str): string

Converts string to upper case with space-separated words.

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Parameters

str: string | null | undefined

The string to convert.

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Returns: string

The upper cased string with words separated by spaces.

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See Also

String.toUpperCase() - MDN

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Since

2.0.0

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Performance

O(n) — charCode word splitting for short ASCII, regex for long/Unicode/emoji.

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Also known as

upperCase (Lodash, es-toolkit) · ❌ (Remeda, Radashi, Ramda, Effect, Modern Dash, Antfu)

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Example

upperCase('--Foo-Bar--');  // => 'FOO BAR'
upperCase('fooBar');       // => 'FOO BAR'
upperCase('__foo_bar__');  // => 'FOO BAR'

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How it works?

Converts string to space-separated uppercase words. Splits on case boundaries, underscores, hyphens, and emojis. Supports Unicode.

Conversion Examples

Input	Output
'--Foo-Bar--'	'FOO BAR'
'fooBar'	'FOO BAR'
'__foo_bar__'	'FOO BAR'

Process

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Use Cases

Convert to upper case words 📌

Convert string to space-separated uppercase words. Useful for headers, labels, or constants display.

#upper#case#words#convert#split

upperCase('fooBar');       // => 'FOO BAR'
upperCase('__foo_bar__');  // => 'FOO BAR'
upperCase('--Foo-Bar--');  // => 'FOO BAR'

Format header text

Format identifiers as uppercase display text.

#format#header#title#display#label#design system

const header = upperCase('contentType');
// => 'CONTENT TYPE'