##### 实例 - 默认用法 ~~~ $back = $T_C->format('100000'); ~~~ >结果: 100,000 ##### 实例 - 限定间距几个字符进行分割 ~~~ $back = $T_C -> format('100000',['space'=>4]); ~~~ >结果: 10,0000 ##### 实例 - 限定分割插入字符 ~~~ $back = $T_C->format('100000',['space'=>4,'str=>'-']); ~~~ >结果:10-0000 ##### 实例 - 针对带小数点的字符串格式化(限v7以上版本) ~~~ $back = $T_C->format('1234567.89',['node'=>2]); ~~~ >结果:10-0000