backgroundPosition property

Artículo
05/02/2017

Specifies the position of the background of the object.

Syntax

Integer value = object.put_backgroundPosition( v);Integer value = object.get_backgroundPosition(* sPosition);

Property values

Type: BSTR

One or two of the values listed in Possible Values.

length

Floating-point number, followed by a supported length unit.

percentage

Integer, followed by a percent sign (%). The value is a percentage of the width or height of the object.

Value	Meaning
0% 0%

vAlignment

Vertical alignment value.

Value	Meaning
top	Vertical alignment is at the top.
center	Vertical alignment is centered.
bottom	Vertical alignment is at the bottom.

hAlignment

Horizontal alignment value.

Value	Meaning
left	Horizontal alignment is to the left.
center	Horizontal alignment is centered.
right	Horizontal alignment is to the right.

String format

[[ percentage | length | left | center | right ][ percentage | length | top | center | bottom ]?]|[[ left | center | right ]||[ top | center | bottom ]]

CSS information

Applies To	All elements
Media	visual
Inherited	no
Initial Value	0% 0%

Standards information

CSS Backgrounds and Borders Module Level 3, Section 3.6

Remarks

If only one value is set, that value applies to the horizontal coordinate, and the vertical is set to "50%". If both values are set, the first value applies to the horizontal coordinate and the second value applies to the vertical.

Setting the values to "0% 0%" (initial value) positions the IHTMLRuleStyle::backgroundImage to the upper left corner of the element's content block, which includes the padding.

Setting the background position using pixels positions the upper-left of the image at the specified x and y coordinates within the parent element. As the coordinates increase, the image moves to the right and down the visible area. By contrast, setting the background position with percentages uses a corresponding point on the image. At a position of "50% 50%" the image is effectively centered within the visible area.

This property can be set with the other background properties using the IHTMLRuleStyle::background composite property.

Starting in Windows Internet Explorer 9, the background of an element can have multiple layers. The number of layers is determined by the number of comma-separated values in the IHTMLRuleStyle::backgroundImage property. Each of the images is sized, positioned, and tiled according to the corresponding value in the other background properties (IHTMLRuleStyle::backgroundAttachment, IHTMLCSSStyleDeclaration::backgroundClip, IHTMLCSSStyleDeclaration::backgroundOrigin, IHTMLRuleStyle::backgroundPosition, IHTMLRuleStyle::backgroundRepeat, and IHTMLCSSStyleDeclaration::backgroundSize). The first image in the list is the layer closest to the user, the next one is painted behind the first, and so on.

The background of an element can have multiple layers. The number of layers is determined by the number of comma-separated values in the IHTMLRuleStyle::backgroundImage property. Each of the images is sized, positioned, and tiled according to the corresponding value in the other background properties (IHTMLRuleStyle::backgroundAttachment, IHTMLCSSStyleDeclaration::backgroundClip, IHTMLCSSStyleDeclaration::backgroundOrigin, IHTMLRuleStyle::backgroundPosition, IHTMLRuleStyle::backgroundRepeat, and IHTMLCSSStyleDeclaration::backgroundSize). The first image in the list is the layer closest to the user, the next one is painted behind the first, and so on.

As of Internet Explorer for Windows Phone 8.1 Update, Internet Explorer for Windows Phone supports "-webkit-background-position" as an alias for this property.

Examples

The following example shows how to use IHTMLRuleStyle::backgroundPosition to specify different background position settings for three div objects.

<body>
   <div class="circle"></div>
   <div class="square"></div>
   <div class="triangle"></div>
</body>

In the first div object, IHTMLRuleStyle::backgroundPosition is set to 90% 50%. This represents a horizontal offset of 90% relative to the width of the object and a vertical offset of 50% relative to its height. In the second div object, the value for IHTMLRuleStyle::backgroundPosition is left bottom, which is equivalent to 0% for the horizontal position and 100% for the vertical position. In the third div object, IHTMLRuleStyle::backgroundPosition is set to 50px 50px, which sets the vertical and horizontal positions at 50 pixels.

div {
   width: 150px;
   height: 150px;
   background-color: #D3D3D3;
}
.circle {
   background-image:url(circle.png);
   background-repeat: no-repeat;
   background-position: 90% 50%;
}
.square {
   background-image:url(square.png);
   background-repeat: no-repeat;
   background-position: left bottom;
}
.triangle {
   background-image:url(triangle.png);
   background-repeat: no-repeat;
   background-position: 50px 50px;
}

Requirements

Minimum supported client	Windows XP
Minimum supported server	Windows Server 2003
Header	Mshtml.h
IDL	Mshtml.idl
DLL	Mshtml.dll

Compartir a través de