Learn PHP - Learn chapter 2

Using PHP

Forms

Form processing:

PHP superglobals: $ _ GET and $ _POST for processing form data (form-data)

<Form> tag Form

The action attribute: URL specified form data submission

method attribute: use when submitting the provisions of the HTTP method (recommended POST)

<Input> tag form element

type property: dynamically defined label box type
```
<!DOCTYPE html>
<html>
<head>
  <title>表单处理</title>
</head>
<body>
  <form action="index.php" method="post">
      Name:<input type="text" name="name" />
      E-mail:<input type="text" name="E-mail" />
      <input type="submit" value="Yes" />
  </form>
</body>
</html>
```
HTML document form data will be submitted to post way to handle php files

Likewise, PHP file to accept a form POST HTML page form submission data

<!DOCTYPE html>
<html>
<head>
  <title>php处理表单</title>
</head>
<body>
  <?php 
      echo $_POST["name"];
      echo "<br />";
      echo $_POST["E-mail"];
   ?>
</body>
</html>

Similarly, the method can also be changed to get the post method to submit the form to be processed form php file

form validation:

<!DOCTYPE html>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 
    <title>表单处理</title>
</head>
<body>
    <form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">
        姓名：
        <input type="text" name="name" />
        <br />
        邮箱：
        <input type="text" name="E-mail" />
        <br />
        网址：
        <input type="text" name="url" />
        <br />
        评论：
        <textarea rows="20px" cols="30px" name="txt"></textarea>
        <br />
        性别：
        <input type="radio" value="男" name="sex" />男
        <input type="radio" value="女" name="sex" />女
        <br />
        <input type="submit" value="Yes" />
    </form>
    <?php 
        function br() {
            echo "<br />";
        }
        echo $_POST["name"] ;
        br();
        echo $_POST["E-mail"];
        br();
        echo $_POST["url"];
        br();
        echo $_POST["txt"];
        br();
        echo $_POST["sex"];
     ?>
</body>
</html>

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$ _SERVER [ "PHP_SELF"] variables:

Super global variables, return the currently executing script file name

htmlspecialchars () Method:

Characters into HTML entities

Dates and times:

Gets the date and time: date ()

语法：string date(string format[,int timestamp])
Arguments: format display format, timestamp is the timestamp

Parameter Value	Explanation
Y	Year 4-digit full representation
m	The numbers indicate the month with leading 0
d	The first day of the month, 2 digits with leading zeros
l (L lowercase)	Day of the week, the full text
N	The first few that week, a string of 1-7
w	The first few days of the week, 0-6
with	The first few days of the year
W	The first few weeks of the year
H	Hour, 24-hour format, with leading zeros
i	There are number of minutes leading zeros
s	The number of seconds, with leading zeros
The	The number of seconds from the Unix epoch to today's

time () function:

Returns the timestamp of the total number of seconds of the current time
Format: int time (void)

microtime () function:

Returns the current time timestamp and microsecond

mktime () function:

Ditto