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Window

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HTML DOM

HTML DocumentsHTML Elements
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alignContentalignItemsalignSelfanimationanimationDelayanimationDirectionanimationDurationanimationFillModeanimationIterationCountanimationNameanimationTimingFunctionanimationPlayStatebackgroundbackgroundAttachmentbackgroundClipbackgroundColorbackgroundImagebackgroundOriginbackgroundPositionbackgroundRepeatbackgroundSizebackfaceVisibilityborderborderBottomborderBottomColorborderBottomLeftRadiusborderBottomRightRadiusborderBottomStyleborderBottomWidthborderCollapseborderColorborderImageborderImageOutsetborderImageRepeatborderImageSliceborderImageSourceborderImageWidthborderLeftborderLeftColorborderLeftStyleborderLeftWidthborderRadiusborderRightborderRightColorborderRightStyleborderRightWidthborderSpacingborderStyleborderTopborderTopColorborderTopLeftRadiusborderTopRightRadiusborderTopStyleborderTopWidthborderWidthbottomboxShadowboxSizingcaptionSidecaretColorclearclipcolorcolumnCountcolumnFillcolumnGapcolumnRulecolumnRuleColorcolumnRuleStylecolumnRuleWidthcolumnscolumnSpancolumnWidthcounterIncrementcounterResetcssFloatcursordirectiondisplayemptyCellsfilterflexflexBasisflexDirectionflexFlowflexGrowflexShrinkflexWrapfontfontFamilyfontSizefontStylefontVariantfontWeightfontSizeAdjustheightisolationjustifyContentleftletterSpacinglineHeightlistStylelistStyleImagelistStylePositionlistStyleTypemarginmarginBottommarginLeftmarginRightmarginTopmaxHeightmaxWidthminHeightminWidthobjectFitobjectPositionopacityorderorphansoutlineoutlineColoroutlineOffsetoutlineStyleoutlineWidthoverflowoverflowXoverflowYpaddingpaddingBottompaddingLeftpaddingRightpaddingToppageBreakAfterpageBreakBeforepageBreakInsideperspectiveperspectiveOriginpositionquotesresizerightscrollBehaviortableLayouttabSizetextAligntextAlignLasttextDecorationtextDecorationColortextDecorationLinetextDecorationStyletextIndenttextOverflowtextShadowtextTransformtoptransformtransformOrigintransformStyletransitiontransitionPropertytransitionDurationtransitionTimingFunctiontransitionDelayunicodeBidiuserSelectverticalAlignvisibilitywidthwordBreakwordSpacingwordWrapwidowszIndex

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Other References

CSSStyleDeclarationJS Conversion


JavaScript Optional Chaning ( ?. )

Example

// Create an object:
const car = {type:"Fiat", model:"500", color:"white"};

// Ask for car name:
document.getElementById("demo").innerHTML = car?.name;
Try it Yourself »

Description

TheOptional Chaning ( ?. ) Operator returnsundefined if an object isundefined ornull (instead of throwing an error).

Browser Support

Optional Chaning is a JavaScript 2020 feature.

ES 2020 is supported in all modern browsers sinceSeptember 2020:

Chrome
85		Edge
85		Firefox
79		Safari
14		Opera
71
Aug 2020Aug 2020Mar 2020Sep 2020Sep 2020


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