Understanding and Implementing Schemas in Python

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Understanding and Implementing Schemas in Python Introduction In the world of programming, particularly in the context of data management and validation, schemas play a vital role. A schema is essentially a blueprint or a predefined structure that defines the expected format, data types, and constraints for a given data entity. In this blog, we will delve into the concept of schemas in Python, exploring what they are, why they are important, and how you can implement them in your projects. What is a Schema? A schema serves as a contract between different components of a system, ensuring that data is consistent, valid, and well-structured. It defines the rules for how data should be organized, what fields it should contain, and what types of values those fields can hold. In essence, a schema acts as a set of rules that data must adhere to in order to be considered valid. Why Are Schemas Important? Data Validation: Schemas provide a way to validate incoming data. When data is received o...
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Create a Simple Calculator App in React Js | Interview Question

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Create a Simple Calculator App in React Js | Interview Question

In this post, you will learn about how to create simple calculator App in React js using hooks.

Following is the UI functionality of the application.

calculator

Sample Code:

A) App.js

import React, { useState } from 'react';
import './style.css';

const Header = () => {
  return <div id="header">Simple Calculator</div>;
};

export default function App() {
  const buttons = [
    { id: 1, name: '7' },
    { id: 2, name: '8' },
    { id: 3, name: '9' },
    { id: 4, name: 'Del' },
    { id: 5, name: '4' },
    { id: 6, name: '5' },
    { id: 7, name: '6' },
    { id: 8, name: '+' },
    { id: 9, name: '1' },
    { id: 10, name: '2' },
    { id: 11, name: '3' },
    { id: 12, name: '-' },
    { id: 13, name: '.' },
    { id: 14, name: '0' },
    { id: 15, name: '/' },
    { id: 16, name: '*' },
  ];
  const [text, setText] = useState('');
  const [show, setShow] = useState('');

  const onClickDel = (name) => {
    let numStr = text.substring(text.length - 1, 0);
    setText(numStr);
  };

  const onClickGeneral = (name) => {
    let numStr = text + name;
    setText(numStr);
  };

  const submit = () => {
    let evalStatement;
    try {
      evalStatement = eval(text);
      setShow(evalStatement);
    } catch (err) {
      setShow('Error');
    }
  };

  const reset = () => {
    setShow('');
    setText('');
  };

  return (
    <div id="mainDiv">
      <Header />
      <input id="input" type="text" value={text} />
      <input id="output" type="text" value={show} />
      <div>
        {buttons &&
          buttons.length &&
          buttons.map((item) => {
            return (
              <div
                id="circle"
                onClick={
                  item.name == 'Del'
                    ? () => {
                        onClickDel(item.name);
                      }
                    : () => {
                        onClickGeneral(item.name);
                      }
                }
                key={item.id}
              >
                {item.name}
              </div>
            );
          })}
      </div>

      <button id="reset" onClick={reset}>
        {' '}
        Reset{' '}
      </button>
      <button id="submit" onClick={submit}>
        {' '}
        Submit{' '}
      </button>
    </div>
  );
}

CSS:

B) styles.css

#mainDiv {
  border: 1px solid black;
  width: 320px;
  height: 330px;
  background-color: orange;
  border-radius: 30px;
}

#reset,
#submit {
  border: 1px solid black;
  float: left;
  width: 80px;
  margin-left: 25px;
  margin-right: 25px;
  margin-top: 10px;
  font-weight: bold;
}

#input,
#output {
  width: 260px;
  height: 30px;
  margin-top: 10px;
  margin-left: 25px;
  margin-right: 25px;
  margin-bottom: 2px;
  border-radius: 5px;
  font-weight: bold;
}

#circle {
  width: 30px;
  height: 30px;
  background-color: rgb(162, 162, 162);
  border-radius: 10px;
  float: left;
  text-align: center;
  margin-top: 10px;
  margin-left: 25px;
  margin-right: 25px;
  margin-bottom: 2px;
  line-height: 30px;
  font-weight: bold;
}

#header {
  margin-left: 25px;
  margin-right: 25px;
  margin-top: 10px;
  text-align: center;
}


Happy Learning!! Happy Coding!!

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