flutter dart语法合并多条List 数组

flutter dart语法合并多条List 的案例

List<dynamic> test1=[];

List<dynamic> test2=[];

List<dynamic> test3=[];

方法1

List<dynamic> test4=[];
 
 
test4..addAll(test1)..addAll(test2)..addAll(test3);

方法2

List<dynamic> test4=[];
 
 
 
test4=[...test1,...test2,...test3,];