Technical overview

OpenLayers is a JavaScript package for developing WebGIS clients. Sources supported by OpenLayers include Google Maps, Yahoo, Map, Microsoft Virtual Earth, etc. Users can also use a simple image map as a background image to overlay other layers in OpenLayers. In this regard, OpenLayers provides a lot of s Choice.

The code implements the function of loading a tile map (ie OpenStreetMap map) and can pan and zoom the map. When initializing a map, you need at least one view, one or more layers, and a target HTML tag for the map to load.

The map element of this example sets its tabindex property to "0", which makes it focusable. To focus on the map element, you can navigate to it using the "Tab" key, or you can use a jump link. When focusing on the map element, the "+" and "-" keys can be used to zoom in and out, and the arrow keys can be used to pan the layer.