有时候需要限制编辑框输入的字符，比如只允许输入字母字符，或者只允许输入数字字符，-sometimes necessary to restrict the importation of the edit box characters, such as only allowing the importation of alphabetical characters, or allow only the importation of digital characters,

一个完整的数字硬盘录像机系统软件，包括视频数据采集与压缩录像；云台控制；接入报警与电子地图。-a complete digital hard drive recorder system software, including video data acquisition and video compression; Tilt control; Alarm and access electronic map.