一 字符串换行
//angular html<div style='padding:20px;white-space:pre'> {{explain}}</div>//tsthis.explain='sdfsdf\n'+' sfsdfsdf\n'+" sdfdsfds"//angular html<div style='padding:20px;white-space:pre'> {{explain}}</div>//tsthis.explain='sdfsdf\n'+' sfsdfsdf\n'+" sdfdsfds"