最近几年来，地理信息系统无论是在理论上还是应用上都处在一个飞速发展的阶段。 GIS被应用于多个领域的建模和决策支持，如城市管理、区划、环境整治等等，地理信息成为信息时代重要的组成部分之一； “数字地球”概念的提出，更进一步推动了作为其技术支撑的GIS的发展。 与此同时，一些学者致力于相关的理论研究，如空间感知、空间数据误差、空间关系的形式化等等。 这恰好说明了地理信息系统作为应用技术和学科的两个方面，并且这两个方面构成了相互促进的发展过程。
In this chapter, we will show you some examples of multimedia queries.
Before we begin, let’s make a list of email links. The HTML code is as follows:
Example 1
Be careful When the width of the browser is from 520 to 699px, add a mail icon before the mailbox link: Example 2 When the width of the browser is 700 to 1000px, “Email:” is added in frontof the mailbox link: Example 3 When the width of the browser is greater than 1001px, an email address connection is added after the link. We’ll use Example 4 When the width of the browser is greater than 1001px, an icon is added in front of the person’s name. In the example, we do not write additional query blocks, we can add other media queries (similar to the OR operator) after the existing query media are separated by commas: Example 5 data-email Property. In HTML we can use the belt data- prefix to store information. 8.22.1. 520 to 699px width-add mailbox icon ¶
@media screen and (max-width: 699px) and (min-width: 520px){ ul li a{ padding-left:30px; background:url(email-icon.png) left center no-repeat; } }
8.22.2. 700 to 1000px-add text prefix information ¶
@media screen and (max-width: 1000px) and (min-width: 700px){ ul li a:before{ content:"Email: "; font-style:italic; color:#666666; } }
8.22.3. Greater than 1001px width-add email address ¶
data- property to add an email address after each person’s name:@media screen and (min-width: 1001px){ ul li a:after{ content:" (" attr(data-email) ")"; font-size:12px; font-style:italic; color:#666666; } }
8.22.4. Greater than 1151px width-add icon ¶
@media screen and (max-width: 699px) and (min-width: 520px), (min-width: 1151px) { ul li a { padding-left: 30px; background: url(email-icon.png) left center no-repeat; } }
