redo php

REDO PHP

why

Could do nothing in hackerSon in ceress.

abstract

xampp,post,get, conn,sql,result, mysqli_query(), mysqli_fetch_assoc(),

exe

open OSX-Manager.app in /App/XMAPP/

o /Applications/XAMPP/manager-osx.app

Open localhost/ by browser
like this:
!(https://i.stack.imgur.com/OCBrm.png)

min

Go to App.../xampp/htdocs/
Then make echo.php
The inside

<?php
echo "HELLO";

And access to localhost/echo.php
to see the result of hello.

POST and GET

GET

Write this and press the btn.

<form method="GET">
    <input type="hidden" name="name" value="Daniel" >
    <button type = 'submit'>PRESS ME</button>
</form>

then url changes from

http://localhost/postget.php

to

http://localhost/postget.php?name=value

This is GET method.

POST

When using POST instead of GET the code above,
The URL does not change.
But print $_POST by echo in php like this:

echo $_POST['name'];

you see the name value Daniel above the btn.

Echoing GET by echo $_GET['name'];
and send name by GET method also returns Dan

conclude

submit by method='post':
$_POST['name'] gain the name's value.
'get',$_GET are the same.

DB

Make a db

login MySQL by mysql -u root
and make a db like this:

CREATE DATABASE hoge;

    CREATE TABLE tableName (
        id int(11) auto_increment primary key not null,
        name VARCHAR(256) NOT NULL,
        price INTEGER ,
        date DATE ,
        PRIMARY KEY (id)
    );

insert records like this:

INSERT INTO tableName (name, price, column3, ...)
VALUES (value1, value2, value3, ...);

print the records

make connecting php file:
includes/dbh.inc.php and write:

$dbServername = "localhost";
$dbUsername = "root";
$dbPassword = "";
$dbName = "loginsystem";

$conn = mysqli_connect(
    $dbServername, $dbUsername, 
    $dbPassword, $dbName
);

Then write printing php:
conn.php:

include_once 'includes/dbh.inc.php';

This first. this make connection.
Next, make sql:
$sql = 'select * from users;';
Then, result:
$result = mysqli_query($conn, $sql);
This $conn is connection written in includes/dbh.inc.php
Finally, print them from $result by:

while($row = mysqli_fetch_assoc($result)) {
    echo $row['name']."<br>";
}

conclude

writing connection file and extend that by

include_once 'includes/dbh.inc.php';

Then make sql var:
$sql = 'select * from users;';
And result:
$result = mysqli_query($conn, $sql);
Finally, take that out from $result:

while($row = mysqli_fetch_assoc($result)) {
    echo $row['name']."<br>";
}

Then this can print every name inside the db.

Refered

https://www.youtube.com/playlist ?list=PL0eyrZgxdwhwBToawjm9faF1ixePexft-