最近需要一个浮点数编辑框。所谓浮点数编辑框，就是限制输入只在”-1234567890.” 这些字符，其它字符不予输入（用户输错了冒一个气泡进行提示）。本想使用BCG库的CBCGPMaskEdit类，无奈该类允许重复输入小数点，不满足我的需求。-Need a floating-point edit box. The so-called floating-point edit box, is to restrict the input prompt " -1234567890"　these characters, other characters will not be input (user input the wrong take a bubble). This BCG library CBCGPMaskEdit class, but unfortunately the class allows you to repeatedly enter the decimal point does not meet my needs.