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SVG <rect>

SVG has some predefined shape elements that can be used and manipulated by developers.

SVG Shapes

SVG has some predefined shape elements that can be used and manipulated by developers:

The following chapters will explain each element, starting with the rect element.

The <rect> tag is used to create a rectangle and variations of a rectangle shape.

To understand how this works, copy the following code into Notepad and save the file as "rect1.svg". Place the file in your Web directory:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">

<rect width="300" height="100"
style="fill:rgb(0,0,255);stroke-width:1;
stroke:rgb(0,0,0)"/>

</svg>

Code explanation:

The width and height attributes of the rect element define the height and the width of the rectangle
The style attribute is used to define CSS properties
The CSS fill property defines the fill color of the rectangle (either an rgb value, a color name, or a hexadecimal value)
The CSS stroke-width property defines the width of the border of the rectangle
The CSS stroke property defines the color of the border of the rectangle

Let's look at another example that contains some new attributes:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">

<rect x="20" y="20" width="250" height="250"
style="fill:blue;stroke:pink;stroke-width:5;
fill-opacity:0.1;stroke-opacity:0.9"/>

</svg>

Code explanation:

The x attribute defines the left position of the rectangle (e.g. x="0" places the rectangle 0 pixels from the left of the browser window)
The y attribute defines the top position of the rectangle (e.g. y="0" places the rectangle 0 pixels from the top of the browser window)
The CSS fill-opacity property defines the opacity of the fill color (legal range: 0 to 1)
The CSS stroke-opacity property defines the opacity of the stroke color (legal range: 0 to 1)

Define the opacity for the whole element:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">

<rect x="20" y="20" width="250" height="250"
style="fill:blue;stroke:pink;stroke-width:5;
opacity:0.9"/>

</svg>

Code explanation:

The CSS opacity property defines the opacity value for the whole element (legal range: 0 to 1)

Last example, create a rectangle with rounded corners:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">

<rect x="20" y="20" rx="20" ry="20" width="250"
height="100" style="fill:red;stroke:black;
stroke-width:5;opacity:0.5"/>

</svg>

Code explanation: