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+

*

==

[]

${}

```dart

/**

*

* @author xgqfrms

* @license MIT

* @copyright xgqfrms

* @created 2019-01-01

*

* @description

* @augments

* @example

*

*/

void main() {

String single_quote = 'signle quote string';

print("single_quote = ${single_quote}");

String double_quote = "double quote string";

print("double_quote = ${double_quote}");

String signle_multi_lines = '''

? ?signle

? ?multi lines

? ?multi lines string

?''';

print("signle_multi_lines = ${signle_multi_lines}");

String double_multi_lines = """

? ?double

? ?multi lines

? ?multi lines string

?""";

print("double_multi_lines = ${double_multi_lines}");

String backslash_n = "string line1\nstring line2\nstring line3";

print("backslash_n = ${backslash_n}");

String raw_string = r"string line1\nstring line2\nstring line3";

print("raw_string = ${raw_string}");

}

```

```dart

dynamic even = 2;

dynamic odd = 3;

print("\neven = ${even.isEven}");

print("odd = ${odd.isOdd}");

// double: static const double nan = 0.0 / 0.0;

// dynamic nan = 0 / 0;

dynamic nan = 0.0 / 0.0;

print("nan = ${nan.isNaN}");

```

屬性: isNaN, isEven, isOdd

even 偶數(shù)

odd?奇數(shù)

方法: abs(), round(), floor(), ceil(), toInt(), toDouble()

~/ 取整

% 取余

/ 除

+

-

* 乘

// Number / num

int

double

// Boolean

bool

String

// Dart 字符串是 UTF-16 編碼的字符序列?？梢允褂脝我柣蛘唠p引號來創(chuàng)建字符串

List

Map

Set

Runes

Symbols

踩個點?。?/p>

Dart 數(shù)據(jù)類型

```dart

/**

*

* @author xgqfrms

* @license MIT

* @copyright xgqfrms

* @created 2019-01-01

*

* @description

* @augments

* @example

*

*/

void main() {

// main() {

print("Hello Dart! ?");

// do something...

// return void;

}

```

/**

*

* @author xgqfrms

* @license MIT

* @copyright xgqfrms

* @created 2019-01-01

*

* @description

* @augments

* @example

*

*/

void main() {

final name = "xgqfrms";

print("final name ${name}");

/*

?name = "dart";

?// Error: Can't assign to the final variable 'name'.

?print("new final name ${name}");

? */

/*

?final year;

?// Error: The final variable ';' must be initialized.

?year = 2018;

?print("final year ${year}");

? */

// return null;

}

https://gitee.com/LeiYu-Io/Dart-Basic

還要注冊才能下載，shit gitee

github 不香嗎？

VS Code

```sh

$?brew tap dart-lang/dart

$ brew install dart

```

https://dart.dev/get-dart

2018.08 Dart 1.x Dart VM version: 2.8.4 (stable) (Wed Jun 3 12:26:04 2020 +0200) on "macos_x64" Flutter

1、Google發(fā)布的開源語言

2、最初是為了代替web語言

3、現(xiàn)在可以支持web開發(fā)、腳本開發(fā)、全平臺開發(fā)，flutter開發(fā)

4、是一門面向?qū)ο笳Z言