//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;2
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;3
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;4
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;5
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;6
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;7
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;8
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;7
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;8
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;7
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;2
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;3
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;4
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;5
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;6
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;7
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;8
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;9
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color0
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;8
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color2
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color3
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;8
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color5
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color6
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color7
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;4
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color9
$textcolor:
0
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;4
$textcolor:
2$textcolor:
3
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;3
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;4
$textcolor:
6//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;4
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;5
$textcolor:
9 //SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;7
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;8
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;9
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color0
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;8
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color2
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color3
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;8
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color5
blue
9$textcolor:
9;
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color7
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;5
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;6
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;7
;
6
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;9
:
blue
;
;
6
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color2
:
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;0_______151_______
;
6
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color5
:
___//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;3
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;4
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;5
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;6
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;7
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;8
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;7
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;8
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;7
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;2
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;3
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color7
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;4
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;5
$textcolor:
9 //SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;7
;
6
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;9
:
blue
;
;
6
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color2
:
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;0_______151_______
;
6
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color5
:
___//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;3
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;4
blue
;
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color7
- Biến toàn cầu. Các biến được khai báo ở đầu tệp là biến toàn cục. e. , bạn có thể sử dụng nó ở bất cứ đâu trong tài liệu
- Biến phạm vi. Các biến, được khai báo trong bất kỳ khối nào, có phạm vi. e. , bạn không thể sử dụng nó bên ngoài phạm vi của khối
- tập tin SASS
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
13//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
14;
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
4//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
5//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
6//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
7//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
8//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
21//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
22;
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
8//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
9//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
26//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
27;
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
8//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color
5:
___//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
3//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
4$
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
27;
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color
7//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
4//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
39_______0_______27//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
41//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
42//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
43//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
6//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
45//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
46//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
47//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
48//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
49_______0_______50//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
4//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
52//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
53//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
54//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
4//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
56//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
6//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
7//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
8//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
39//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
27//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
62//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
8//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
9//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
65//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
4//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
8//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
68//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
8//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color
5:
___//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
3//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
4//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
74//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color
7 - Tệp CSS đã biên dịch
Có nhiều khái niệm hơn về biến, như Shadowing của biến, giá trị mặc định của biến, Khai báo điều khiển luồng của biến. Hãy thảo luận về chúng bên dưới từng cái một
Giá trị mặc định của biến
SASS cho phép người dùng khai báo một số giá trị mặc định cho các biến có thể được sử dụng nếu biến không được khai báo hoặc được gán giá trị 'null'. Nếu một biến được khai báo với một số giá trị, thì giá trị đó sẽ được ghi đè lên giá trị mặc định. Trong SASS, biến mặc định được gán với. thẻ mặc định
Cú pháp của biến mặc định
$color: black !default ; //black is the default value to the variable 'color'
Shadowing của các biến
Trong SASS, người ta có thể viết hai biến có cùng tên. một toàn cầu và một địa phương. Trong điều kiện như vậy, người dùng có thể thay đổi nhầm giá trị của biến toàn cục bằng cách thay đổi giá trị của biến cục bộ. Để tránh tình trạng như vậy, SASS có tính năng tạo bóng, trong đó khi viết một biến cục bộ bên trong phạm vi cục bộ không nhất thiết phải thay đổi giá trị của biến toàn cục
Đưa ra dưới đây là một ví dụ để hiển thị các chức năng trên
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;
Đoạn mã trên khi được biên dịch thành CSS gốc sẽ trở thành
CSS
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;76
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;77
:
blue
;
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color7
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;82
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;77
:
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;85
;
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color7
Bây giờ, để thay đổi giá trị của biến toàn cục từ phạm vi cục bộ, chúng ta cần đề cập đến “. thẻ toàn cầu” bên cạnh biến như hình bên dưới
//SASS Code file\ $colour: black; .nav $colour: blue !global; background-color: $colour; .p background-color: $colour;
Đoạn mã trên khi được biên dịch thành CSS gốc sẽ trở thành
CSS
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;76
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;77
:
blue
;
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color7
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;82
//SASS Code file $colour: black; .nav $colour: blue; background-color: $colour; .p background-color: $colour;77
:
blue
;
//SASS Code file $bool: true; $font_color: blue; $bg_color: skyblue; @if $bool $font_color: violet; $bg_color: pink; .nav background-color: $bg_color color: $font_color7
Quy tắc kiểm soát dòng chảy của các biến
Flow Control Scope giúp xác định giá trị của các biến dựa trên luồng của chương trình. Chúng làm cho mã dễ hiểu hơn nhiều và làm cho mã giống như các ngôn ngữ lập trình khác như Java, C++, v.v. Nó thay đổi giá trị của một số biến dựa trên giá trị của một số biến hoặc tính năng khác. Đưa ra dưới đây là một mã ví dụ hiển thị các quy tắc điều khiển luồng của các biến