break和continue

• 终止循环：break

• 跳出当前循环：continue                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
  

while语句

• while循环

• do...while循环

循环语句

• for循环

• for...in循环
  

条件语句

• if语句

• if...else if语句

• if...else if...else语句
  

条件表达式

• 三目运算符:condition?expr1:expr2

• ??运算符：expr1??expr2

??意思是如果左边变量没有值，是空的，就使用后面的值，如果这边变量本来有值，就显示本来的值

赋值运算符

• 基础运算符：=，？？=

• 复合运算符；+=,-=,*=,/=,%=,~/=

??=意思是如果左边变量没有值，是空的，就使用后面的值，如果变量本来有值，那右边是无效的

逻辑运算符

• 运算符：！,&&,||
  

• 针对布尔类型运算

关系运算符

• 运算符:==,!=,>,<,>=,<=

• 判断内容是否相同使用==
  

运算符

算术运算符

• 加减乘除：+,-,*,/,~/,%

• 递增递减:++var,var++,--var,var--

void main(){

var a;

a = 10;

a = "Dart";

dynamic b =20;

b = "javaScript";

var list = new List<dynamic>();

list.add(1);

list.add("hello");

list.add(true);

print(list);

}

Map

Map创建

• 创建Map;var language = {'first'：'Dart','second':'java'}；

• 创建不可变Map:var language = const{'first':'Dart','second':'java'};

• 构造创建:var language = new Map();

常用操作

• [],length

• isEmpty(),isNotEmpty()

• Keys,values

• containsKey(),containsValue()

• remove()

• forEach()
  

List(数组）创建

• 创建List：var list[1,2,3];

• 创建不可变的List：var list = const [1,2,3];

• 构造创建：var list=new  List();

常用操作

• [],length

• add(),insert()

• remove(),clear()

• indexOf(),lastIndexOf()

• sort(),sublist()

• shuffle(),asMap(),forEach()

• 
  

布尔型

• 使用bool表示布尔类型

• 布尔值只有true和false
  

字符串-String

• 使用单引号，双引号创建字符串

• 使用三个引号或双引号创建多行字符串

• 使用r创建原始raw字符串

字符串操作

• 运算符：+，*，==，[]

• 插值表达式：${expression}

• 常用属性；length，isEmpty，isNotEmpty

常用方法

• contains()，subString()

• startsWith()，endsWIthink()

• indexOf()，lastIndexOf()

• toLowerCase()，toUpperCase()

• trim()，trimLeft()，trimRight()

• split(),replaceXXX()