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alignContent alignItems alignSelf animation animationDelay animationDirection animationDuration animationFillMode animationIterationCount animationName animationTimingFunction animationPlayState background backgroundAttachment backgroundColor backgroundImage backgroundPosition backgroundRepeat backgroundClip backgroundOrigin backgroundSize backfaceVisibility border borderBottom borderBottomColor borderBottomLeftRadius borderBottomRightRadius borderBottomStyle borderBottomWidth borderCollapse borderColor borderImage borderImageOutset borderImageRepeat borderImageSlice borderImageSource borderImageWidth borderLeft borderLeftColor borderLeftStyle borderLeftWidth borderRadius borderRight borderRightColor borderRightStyle borderRightWidth borderSpacing borderStyle borderTop borderTopColor borderTopLeftRadius borderTopRightRadius borderTopStyle borderTopWidth borderWidth bottom boxShadow boxSizing captionSide caretColor clear clip color columnCount columnFill columnGap columnRule columnRuleColor columnRuleStyle columnRuleWidth columns columnSpan columnWidth counterIncrement counterReset cursor direction display emptyCells filter flex flexBasis flexDirection flexFlow flexGrow flexShrink flexWrap cssFloat font fontFamily fontSize fontStyle fontVariant fontWeight fontSizeAdjust height isolation justifyContent left letterSpacing lineHeight listStyle listStyleImage listStylePosition listStyleType margin marginBottom marginLeft marginRight marginTop maxHeight maxWidth minHeight minWidth objectFit objectPosition opacity order orphans outline outlineColor outlineOffset outlineStyle outlineWidth overflow overflowX overflowY padding paddingBottom paddingLeft paddingRight paddingTop pageBreakAfter pageBreakBefore pageBreakInside perspective perspectiveOrigin position quotes resize right scrollBehavior tableLayout tabSize textAlign textAlignLast textDecoration textDecorationColor textDecorationLine textDecorationStyle textIndent textOverflow textShadow textTransform top transform transformOrigin transformStyle transition transitionProperty transitionDuration transitionTimingFunction transitionDelay unicodeBidi userSelect verticalAlign visibility width wordBreak wordSpacing wordWrap widows zIndex

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Other References

CSSStyleDeclaration JS Conversion


Stringa JavaScript charCodeAt()

Esempi

Ottieni l'Unicode del primo carattere in una stringa:

let text = "HELLO WORLD";
let code = text.charCodeAt(0);

Ottieni l'Unicode del secondo:

let text = "HELLO WORLD";
let code = text.charCodeAt(1);

Altri esempi di seguito.


Definizione e utilizzo

Il charCodeAt()metodo restituisce l'Unicode del carattere in corrispondenza di un indice (posizione) specificato in una stringa.

L'indice del primo carattere è 0, il secondo è 1, ....

L'indice dell'ultimo carattere è la lunghezza della stringa - 1 (vedi esempi sotto).

Vedi anche il charAt()metodo.

Nota

Per ulteriori informazioni sui set di caratteri Unicode, visita il nostro Riferimento Unicode .


Sintassi

string.charCodeAt(index)

Parametri

Parameter Description
indexOptional. A number.
The index (position) of a character.
Default value = 0.

Valore di ritorno

Tipo Descrizione
Un numeroUnicode del carattere in corrispondenza dell'indice specificato.
NaN se l'indice non è valido.


Altri esempi

Ottieni l'Unicode dell'ultimo carattere in una stringa:

let text = "HELLO WORLD";
let code = text.charCodeAt(text.length-1);

Ottieni l'Unicode del 15° carattere:

let text = "HELLO WORLD";
let code = text.charCodeAt(15);

Supporto browser

charCodeAt()è una funzione ECMAScript1 (ES1).

ES1 (JavaScript 1997) è completamente supportato in tutti i browser:

Chrome IE Edge Firefox Safari Opera
Yes Yes Yes Yes Yes Yes