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how to fix phpmyadmin access denied

Find config.inc file under C:\wamp\apps\phpmyadmin3.5.1 Inside this file find this one line

$cfg['Servers'][$i]['password'] =";

and replace it with

$cfg['Servers'][$i]['password'] = 'Type your root password here';

What is an Undefined Index PHP Error? How to Fix It?

1. Adding Code at the Top of the Page

A simple way to ask PHP to disable reporting of notices is to put a line of code at the beginning of the PHP page.

Code:

<?php error_reporting (E_ALL ^ E_NOTICE); ?>

Or you can add the following code which stops all the error reporting,

<?php error_reporting(0); ?>

2. Changes in php.ini

Php.ini is a configuration file and is essential for all the programs running on PHP. Open this file and find the field error_reporting. The easiest way is to use the ctrl + F shortcut key. By default, error reporting is set to E_ALL. That means all errors are reported. Change this to E_ALL & ~E_NOTICE. It means all errors except for the notices will now be reported.

What is preflight requests in Angular

Answer:

The preflight is being triggered by your Content-Type of application/json. The simplest way to prevent this is to set the Content-Type to be text/plain in your case. application/x-www-form-urlencoded & multipart/form-data Content-Types are also acceptable, but you'll of course need to format your request payload appropriately.

If you are still seeing a preflight after making this change, then Angular may be adding an X-header to the request as well.

Or you might have headers (Authorization, Cache-Control...) that will trigger it, see:

----

Unlike simple requests, for "preflighted" requests the browser first sends an HTTP request using the OPTIONS method to the resource on the other origin, in order to determine if the actual request is safe to send. Such cross-origin requests are preflighted since they may have implications for user data.

The following is an example of a request that will be preflighted:

const xhr = new XMLHttpRequest();
xhr.open("POST", "https://bar.other/doc");
xhr.setRequestHeader("X-PINGOTHER", "pingpong");
xhr.setRequestHeader("Content-Type", "text/xml");
xhr.onreadystatechange = handler;
xhr.send("<person><name>Arun</name></person>");

The example above creates an XML body to send with the POST request. Also, a non-standard HTTP X-PINGOTHER request header is set. Such headers are not part of HTTP/1.1, but are generally useful to web applications. Since the request uses a Content-Type of text/xml, and since a custom header is set, this request is preflighted.

origin 'http://localhost:4200' has been blocked by CORS policy in Angular12

Solution 1 - you need to change your backend to accept your incoming requests

Solution 2 - using Angular proxy see here

Please note this is only for ng serve, you can't use proxy in ng build

Solution 3 - IF your backend accepts requests from a wildcard domanin like *.testdomain.example then you can edit your hosts file and add 127.0.0.1 local.testdomain.example in there, then in your browser instead of localhost:4200 enter local.testdomain.example:4200

Note: the reason it's working via postman is postman doesn't send preflight requests while your browser does.

EXCEPTIONAL DATA REPORT (EDR) STATUS

Check EDR status Click

why we use header in top HTML

The <header> element represents a container for introductory content or a set of navigational links. A <header> element typically contains: one or more heading elements (<h1> - <h6>) logo or icon.

For Example

<!DOCTYPE html>

<html>

<body>

<h1>A heading here</h1>

<p>Posted by John Doe</p>

<p>Some additional information here</p>

</header>

<p>Lorem Ipsum dolor set amet....</p>

</article>

</body>

</html>

app not installed as package appears to be invalid.

Solution

Step 1 : Start Android Studio

Step 2 : Go to Build -> Build Bundles

Step 3 : Select Build APK

Step 4 : Build APK file

How to Rename an Object's Key in JavaScript | Demo | Example

Demo URl

Code Example Here

function renameKeys(obj, newKeys) {

  const keyValues = Object.keys(obj).map(key => {
    const newKey = newKeys[key] || key;
    return { [newKey]: obj[key] };
  });
  return Object.assign({}, ...keyValues);
}

Uses

 const obj = { a: "1", b: "2" };

const newKeys = { a: "A", c: "C" };
const renamedObj = renameKeys(obj, newKeys);
console.log(renamedObj);

// {A:"1", b:"2"}

How many ways to create Objects in JavaScript

We can 5 ways to create objects in JavaScript.

Lets understand how to Create it...

Demo URL

'use strict';

Example 1

var fruit = {};
fruit.name = 'Mango';
fruit.color = 'Yellow';
console.log(`fruit name ${fruit.name} and color is ${fruit.color}`);

Example 2

var fruit2 = { name: 'Mango', color: 'Yellow' };
console.log(`fruit name ${fruit2.name} and color is ${fruit2.color}`);

function Fruit(name, color) {
  (this.name = name), (this.color = color);
}

Example 3

var fruit3 = new Fruit('Mango', 'Yellow');

Example 4

var fruit4 = new Fruit('Donut', 'Sprinkled Yellow');

console.log(`fruit name ${fruit3.name} and color is ${fruit3.color}`);
console.log(`fruit name ${fruit4.name} and color is ${fruit4.color}`);

console.log(`Check fruit3 proto ${Fruit.prototype === fruit3.__proto__}`);

// console.log(`Property descriptor
// ${JSON.stringify(Object.getOwnPropertyDescriptor(fruit,'name'))}`)

Example 5

var fruit5 = Object.create(Object.prototype, {
  name: {
    value: 'Mango',
    enumerable: true,
    writable: true,
    configurable: true,
  },

  color: {
    value: 'Yellow',
    enumerable: true,
    writable: true,
    configurable: true,
  },
});

console.log(`fruit name ${fruit5.name} and color is ${fruit5.color}`);
console.log(`Check fruit3 proto ${fruit.prototype === fruit5.__proto__}`);

var fruit6 = Object.create(Object.prototype, {
  name: {
    value: 'Mango',
    enumerable: true,
    writable: true,
    configurable: true,
  },

  color: {
    value: 'Yellow',
    enumerable: true,
    writable: false,
    configurable: true,
  },
});

fruit6.name = 'Sausages';
//compile error comment it later
//fruit6.color="Red";

for (var props in fruit6) {
  console.log(`${props} : ${fruit6.color}`);
}

console.log(
  `Fruit name ${fruit6.name} and color is ${
    fruit6.color
  } and proto ${JSON.stringify(fruit6.__proto__)}`
);

//Getter Setter

var fruit7 = {
  color: 'Yellow',
  get fruitcolor() {
    return this.color;
  },
  set fruitcolor(val) {
    this.color = val;
  },
};

console.log(`Fruit default color is ${fruit7.fruitcolor}`);

fruit7.fruitcolor = 'Yellow';

console.log(`Fruit changed color is ${fruit7.fruitcolor}`);

console.log(`Check Fruit3 proto ${Fruit.prototype === fruit3.__proto__}`);

What is the difference between Components and Directives?

Demo URL

@Components	@Directives
For register component we use @Component meta-data annotation.	For register directives we use @Directive meta-data annotation.
Component is a directive which use shadow DOM to create encapsulate visual behavior called components. Components are typically used to create Ul widgets.	Directives are used to add behavior to an existing DOM element.
Component is used to break up the application into smaller components.	Directive is used to design reusable components.
Only one component can be present per DOM element.	Many directive can be used in a per DOM element
Component is used to define pipes	You can't define Pipes in a directive.
@View decorator or templateurl template are mandatory in the component.	Directives don't have a View.

What is the difference between constructor and ngOnInit? | Demo | Example

Demo URL

Constructor	ngOninit
A constructor is not the concept of Angular. It is the concept of JavaScript's class.	ngOninit is the second stage of Angular component lifecycle hook whenever is called when angular is done which creating the component.
Constructor is best place to add all dependencies	ngOninit function which guarantees you that the component has already been created.
Constructor is automatically called at the time of creating the object of the class.	Invoked by Angular when component is initialized
Used for Injecting dependencies	Actual business logic performed
we should use constructor() to setup Dependency Injection	is a better place to write "actual work code" that we need to execute as soon as the class is instantiated.