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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


Metoda HTML DOM hasAttribute().

❮ Objekt prvku

Příklad

Zjistěte, zda má prvek <button> atribut onclick:

var x = document.getElementById("myBtn").hasAttribute("onclick");

Další příklady „Vyzkoušejte si to sami“ níže.


Definice a použití

Metoda hasAttribute() vrátí hodnotu true, pokud zadaný atribut existuje, jinak vrátí hodnotu false.

Tip: Pomocí setAttribute() přidejte nový atribut nebo změňte hodnotu existujícího atributu u prvku.


Podpora prohlížeče

Čísla v tabulce určují první verzi prohlížeče, která tuto metodu plně podporuje.

Method
hasAttribute() Yes 9.0 Yes Yes Yes

Syntax

element.hasAttribute(attributename)

Parametry

Parameter Type Description
attributename String Required. The name of the attribute you want to check if exists


Technické údaje

Návratová hodnota: Boolean, vrací true, pokud má prvek atributy, jinak false
Verze DOM Základní objekt prvku úrovně 2

Další příklady

Příklad

Zjistěte, zda má prvek <a> atribut target. Pokud ano, změňte hodnotu cílového atributu na "_self":

// Get the <a> element with id="myAnchor"
var x = document.getElementById("myAnchor"); 

// If the <a> element has a target attribute, set the value to "_self"
if (x.hasAttribute("target")) {      
  x.setAttribute("target", "_self");
}

Související stránky

HTML kurz: HTML atributy

Odkaz HTML DOM: metoda getAttribute() .

Odkaz HTML DOM: metoda removeAttribute().

Odkaz HTML DOM: metoda setAttribute().


❮ Objekt prvku