PDFElement: placeholder property

Value

An object with one property:

aspectRatio

A string: this element's own value, or "" when it has none (and inherits):

A paper name

A4, letter, A5, B5, legal, tabloid and the other names of paper.rt.ht, in any case: the box has that paper's size.

A ratio

Such as 16/9 or 1.5: the box has that shape and the area of the visitor's paper, so 297/210 is A4 in landscape.

-

No box: the page has no size until its PDF arrives.

The attribute is multi-homed: it works on the WebPDF <script>, on every <pdf-file> and on every <pdf-page>, and the nearest one wins.

Without any, the box is the paper of the visitor's region (US Letter in the Americas' letter countries, A4 elsewhere). A size remembered from an earlier visit and pdf-page { --width; --height } come first. See Lazy pages and placeholders.

Examples

Reserving A4 boxes for every page

<script src=//new.webpdf.pro/.js type=module placeholder:aspect-ratio=A4></script>

Slides

document.querySelector("pdf-file").placeholder.aspectRatio = "16/9";

Specifications

Not part of any specification. <pdf-file> and <pdf-page> are autonomous custom elements defined by WebPDF.pro.

Browser compatibility

See also

• Lazy pages and placeholders
• PDFPageElement.loading