mysql 如何存储rgba颜色字段

MySQL 可以使用 VARCHAR 或者 CHAR 类型来存储 RGBA 颜色字段，但是这样存在一定的问题，比如难以进行颜色相关的排序和过滤。更好的方式是使用 INT 类型，将 R、G、B、A 四个值分别存储在整数的四个字节中，再将它们合并成一个 32 位的整数值。这样可以方便地进行排序和过滤，也可以减小数据存储的空间。在应用程序中，可以使用位运算和移位操作来提取 R、G、B、A 值。

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{"pid":-1,"layers":[{"component":{"id":"21de350a-9acc-4fc1-9290-b53b0f3e6939","name":"方块翻牌器","alias":"Cubeflop","version":"v1.0.0","thumbnail":"images/widgets/tools/tool/cubeflop.png","width":450,"height":60,"pnode":{"type":"tool","pnode":{"type":"tools"}},"option":{"suffix":"/ppm","duration":300,"prefix":"NO₂","decimals":1,"textStyle":{"fontSize":30,"color":"rgba(61, 156, 255, 1)","textShadow":{"show":false,"x":0,"y":0,"value":14,"color":"rgba(15, 146, 255, 1)"},"colorSecondary":"rgba(221, 221, 221,1)","fontWeight":"bold"},"backgroundColor":"rgba(8, 21, 39, 1)"},"source":[{"name":"default","source":{"type":"mysql","filter":{"isFilter":false,"filterId":-1},"isAutoUpdate":true,"autoUpdateTime":6,"mapping":[{"name":"value","required":true,"description":"值","type":"number","mapping":"value"}],"static":[{"value":1234.56}],"api":{"sourcesId":-1,"requestType":"GET","requestHeader":{"token":null},"getParam":"","postParam":{},"requestUrl":"","cookie":false,"postMethods":"raw"},"mysql":{"sourcesId":"ea93b0c0-ff44-11ed-a2ea-8fe1718b947a","database":"jxjk","sql":"SELECT*from device_data_update WHERE id =12","sources":{"id":"ea93b0c0-ff44-11ed-a2ea-8fe1718b947a","name":"测试","description":"","host":"192.168.2.66","port":3306,"user":"root","password":"123"}},"elasticsearch":{"sourcesId":-1,"query":{"index":"_all"}},"mongodb":{"sourcesId":-1,"query":{},"collection":-1},"csv":{}}}]},"id":"3f8433b2-1902-4141-8b17-fc36a9a1001c","name":"图层-17-副本(6)","type":"layer","left":29.091,"top":775,"width":450,"height":50,"widthHeightLink":false,"zIndex":8,"locked":false,"visible":true,"opacity":1,"rotate":0,"rotateX":0,"rotateY":0,"mixBlendMode":null,"background":{"color":"rgba(255, 255, 255, 0)"},"border":{"width":0,"color":"#2ed64a","style":"solid"},"radius":{"value":0},"shadow":{"show":false,"color":"rgba(132, 132, 132, 1)","value":5,"ambiguity":10,"x":3,"y":2},"padding":{"value":0},"animation":"","animations":[],"baseLeft":1220,"baseTop":515,"randomRgbaColor":"rgba(255,255,255,0.2)","rightX":506.364,"rightY":781.81}]} 在JavaScript中只留下value一个字段、

可以使用以下代码将value字段提取出来：

const data = {"pid":-1,"layers":[{"component":{"id":"21de350a-9acc-4fc1-9290-b53b0f3e6939","name":"方块翻牌器","alias":"Cubeflop","version":"v1.0.0","thumbnail":"images/widgets/tools/tool/cubeflop.png","width":450,"height":60,"pnode":{"type":"tool","pnode":{"type":"tools"}},"option":{"suffix":"/ppm","duration":300,"prefix":"NO₂","decimals":1,"textStyle":{"fontSize":30,"color":"rgba(61, 156, 255, 1)","textShadow":{"show":false,"x":0,"y":0,"value":14,"color":"rgba(15, 146, 255, 1)"},"colorSecondary":"rgba(221, 221, 221,1)","fontWeight":"bold"},"backgroundColor":"rgba(8, 21, 39, 1)"},"source":[{"name":"default","source":{"type":"mysql","filter":{"isFilter":false,"filterId":-1},"isAutoUpdate":true,"autoUpdateTime":6,"mapping":[{"name":"value","required":true,"description":"值","type":"number","mapping":"value"}],"static":[{"value":1234.56}],"api":{"sourcesId":-1,"requestType":"GET","requestHeader":{"token":null},"getParam":"","postParam":{},"requestUrl":"","cookie":false,"postMethods":"raw"},"mysql":{"sourcesId":"ea93b0c0-ff44-11ed-a2ea-8fe1718b947a","database":"jxjk","sql":"SELECT*from device_data_update WHERE id =12","sources":{"id":"ea93b0c0-ff44-11ed-a2ea-8fe1718b947a","name":"测试","description":"","host":"192.168.2.66","port":3306,"user":"root","password":"123"}},"elasticsearch":{"sourcesId":-1,"query":{"index":"_all"}},"mongodb":{"sourcesId":-1,"query":{},"collection":-1},"csv":{}}}]},"id":"3f8433b2-1902-4141-8b17-fc36a9a1001c","name":"图层-17-副本(6)","type":"layer","left":29.091,"top":775,"width":450,"height":50,"widthHeightLink":false,"zIndex":8,"locked":false,"visible":true,"opacity":1,"rotate":0,"rotateX":0,"rotateY":0,"mixBlendMode":null,"background":{"color":"rgba(255, 255, 255, 0)"},"border":{"width":0,"color":"#2ed64a","style":"solid"},"radius":{"value":0},"shadow":{"show":false,"color":"rgba(132, 132, 132, 1)","value":5,"ambiguity":10,"x":3,"y":2},"padding":{"value":0},"animation":"","animations":[],"baseLeft":1220,"baseTop":515,"randomRgbaColor":"rgba(255,255,255,0.2)","rightX":506.364,"rightY":781.81}]};

const value = data.layers[0].component.source[0].source.static[0].value;

console.log(value); // 输出 1234.56

使用python，MySQL，HTML，css，JavaScript等编程语言，完成一个注册登录界面

好的，以下是一个简单的注册登录界面的示例代码，使用Python Flask框架、MySQL数据库和HTML/CSS/JavaScript编程语言：

1. 创建MySQL数据库

首先需要在MySQL中创建一个名为“users”的数据库，并在其中创建一个名为“users”的表，表格包含以下字段：

- id：自增长的整数类型，作为主键。
- username：varchar类型，用户名。
- password：varchar类型，密码。

可以使用以下SQL语句在MySQL中创建该表：

CREATE DATABASE users;
USE users;
CREATE TABLE users (
  id INT AUTO_INCREMENT PRIMARY KEY,
  username VARCHAR(50) NOT NULL,
  password VARCHAR(50) NOT NULL
);

2. 创建Python Flask应用

安装Python Flask框架和MySQL连接模块pymysql：

pip install flask pymysql

在Python中编写以下代码，创建一个简单的Flask应用：

from flask import Flask, render_template, request, session, redirect
import pymysql

app = Flask(__name__)
app.secret_key = 'secret_key'

# MySQL数据库配置
db = pymysql.connect(
    host='localhost',
    user='root',
    password='',
    db='users',
    charset='utf8mb4',
    cursorclass=pymysql.cursors.DictCursor
)

# 首页
@app.route('/')
def index():
    if 'username' in session:
        return 'Hello, ' + session['username'] + '!<br><a href="/logout">Logout</a>'
    else:
        return redirect('/login')

# 登录页面
@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        username = request.form['username']
        password = request.form['password']
        cursor = db.cursor()
        cursor.execute('SELECT * FROM users WHERE username=%s AND password=%s', (username, password))
        user = cursor.fetchone()
        if user:
            session['username'] = user['username']
            return redirect('/')
        else:
            return render_template('login.html', error='Invalid username or password!')
    else:
        return render_template('login.html')

# 注册页面
@app.route('/register', methods=['GET', 'POST'])
def register():
    if request.method == 'POST':
        username = request.form['username']
        password = request.form['password']
        cursor = db.cursor()
        cursor.execute('SELECT * FROM users WHERE username=%s', (username,))
        user = cursor.fetchone()
        if user:
            return render_template('register.html', error='Username already exists!')
        else:
            cursor.execute('INSERT INTO users (username, password) VALUES (%s, %s)', (username, password))
            db.commit()
            session['username'] = username
            return redirect('/')
    else:
        return render_template('register.html')

# 注销
@app.route('/logout')
def logout():
    session.pop('username', None)
    return redirect('/login')

if __name__ == '__main__':
    app.run(debug=True)

3. 创建HTML/CSS/JavaScript页面

在templates文件夹下创建login.html和register.html两个页面。

login.html页面代码：

<!DOCTYPE html>
<html>
<head>
  <title>Login</title>
  <style>
    body {
      font-family: Arial, sans-serif;
      margin: 0;
      padding: 0;
    }
    form {
      margin: 50px auto;
      width: 300px;
      padding: 20px;
      background-color: #f5f5f5;
      border-radius: 10px;
      box-shadow: 0 0 10px rgba(0, 0, 0, 0.2);
    }
    input[type="text"], input[type="password"] {
      width: 100%;
      padding: 10px;
      margin-top: 10px;
      border: 1px solid #ccc;
      border-radius: 5px;
      box-sizing: border-box;
    }
    input[type="submit"] {
      display: block;
      margin-top: 20px;
      padding: 10px;
      background-color: #4CAF50;
      color: #fff;
      border: none;
      border-radius: 5px;
      cursor: pointer;
    }
    input[type="submit"]:hover {
      background-color: #3e8e41;
    }
    .error {
      color: red;
      margin-top: 10px;
    }
  </style>
</head>
<body>
  <form method="post">
    <h1>Login</h1>
    {% if error %}
    <p class="error">{{ error }}</p>
    {% endif %}
    <input type="text" name="username" placeholder="Username" required>
    <input type="password" name="password" placeholder="Password" required>
    <input type="submit" value="Login">
  </form>
</body>
</html>

register.html页面代码：

<!DOCTYPE html>
<html>
<head>
  <title>Register</title>
  <style>
    body {
      font-family: Arial, sans-serif;
      margin: 0;
      padding: 0;
    }
    form {
      margin: 50px auto;
      width: 300px;
      padding: 20px;
      background-color: #f5f5f5;
      border-radius: 10px;
      box-shadow: 0 0 10px rgba(0, 0, 0, 0.2);
    }
    input[type="text"], input[type="password"] {
      width: 100%;
      padding: 10px;
      margin-top: 10px;
      border: 1px solid #ccc;
      border-radius: 5px;
      box-sizing: border-box;
    }
    input[type="submit"] {
      display: block;
      margin-top: 20px;
      padding: 10px;
      background-color: #4CAF50;
      color: #fff;
      border: none;
      border-radius: 5px;
      cursor: pointer;
    }
    input[type="submit"]:hover {
      background-color: #3e8e41;
    }
    .error {
      color: red;
      margin-top: 10px;
    }
  </style>
</head>
<body>
  <form method="post">
    <h1>Register</h1>
    {% if error %}
    <p class="error">{{ error }}</p>
    {% endif %}
    <input type="text" name="username" placeholder="Username" required>
    <input type="password" name="password" placeholder="Password" required>
    <input type="submit" value="Register">
  </form>
</body>
</html>

4. 运行应用

在命令行中运行以下命令启动应用：

python app.py

在浏览器中访问http://localhost:5000/即可看到登录页面，点击注册按钮即可进入注册页面。注册成功后即可返回首页并显示用户的用户名，点击注销可以退出登录。