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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


Documento HTML DOM getElementById()

Esempio

Ottieni l'elemento con l'id specificato:

document.getElementById("demo");

Ottieni l'elemento e cambia il suo colore:

const myElement = document.getElementById("demo");
myElement.style.color = "red";

O semplicemente cambiarne il colore:

document.getElementById("demo").style.color = "red";

Definizione e utilizzo

Il getElementById()metodo restituisce un elemento con un valore specificato.

Il getElementById()metodo restituisce nullse l'elemento non esiste.

Il getElementById()metodo è uno dei metodi più comuni nel DOM HTML. Viene utilizzato quasi ogni volta che si desidera leggere o modificare un elemento HTML.

Nota

Qualsiasi ID dovrebbe essere univoco, ma:

Se esistono due o più elementi con lo stesso IDgetElementById() , restituisce il primo.

Guarda anche:

Il metodo Document getElementsByTagName()

Il metodo Document getElementsByClassName()

Il metodo Document querySelector()

Il metodo Document querySelectorAll()



Sintassi

document.getElementById(elementID)

Parametri

Parameter Description
id Required.
The id value of an element.

Valore di ritorno

Tipo Descrizione
OggettoL'elemento con l'id specificato.
nullse l'elemento non esiste.

Pagine correlate:

Esercitazione CSS: sintassi CSS

Riferimento CSS: Selettore CSS #id

Riferimento HTML DOM: Proprietà ID HTML DOM

Riferimento HTML DOM: Oggetto stile HTML DOM


Supporto browser

document.getElementById()è una funzionalità DOM di livello 2 (2001).

È completamente supportato in tutti i browser:

Chrome IE Edge Firefox Safari Opera
Yes 9-11 Yes Yes Yes Yes