声明String Builder串 使用new创建并初始化String Builder>对象 StringBuilder sb new StringBuilder("Hello"); ■设置String Builder2容量 StringBuilder sb2 new StringBuilder(100); StringBuilder sb3 new StringBuilder("Hello",100); StringBuilder sb new StringBuilder("Hello"); sb.Capacity 100; 13 13 声明StringBuilder串 ▪ 使用new创建并初始化StringBuilder对象 ▪ 设置StringBuilder容量