PHP class fifth automatic type conversion and Process Control

Study Summary:

1. Understand what automatic type conversions are

2. Understanding Basic Process Control Statements

3. Example: Implementing a Calendar Table

Automatic type conversion

1) integer-to-string

echo $num. " ABC ";

2) string-to-integer
$str +3;
3) Turn Boolean type
False case 0 "" "0" false array () NULL undefined


4) Forced type conversion

(int) $str (float) $str (string) $str

5) Constants

Define ("HOST", "localhost");

6) operator
① One Dollar
++ --


② two Yuan
= - *  / %
= += -= *= /= %=
> >= < <= = = = = = = = =!==
&& | | !


③ Sanyuan
? :


Process Control:
1. Process Control
2. Functions




Process Control:


I. Branching structure
If...elseif....else
Switch...case
If the condition is a fixed value, use the switch statement


Two. Cycle control
For
While


Three. Abort the loop
Break: Direct End

<? PHP header ("Content-type:text/html;charset=utf-8"), for ($i =1, $i <10; $i + +) {if ($i ==3) {break;} Else{echo $i. " <br> ";}}? >//1 2

Continue: End of this cycle

<? PHP header ("Content-type:text/html;charset=utf-8"), for ($i =1, $i <10; $i + +) {if ($i ==3) {continue;} Else{echo $i. " <br> ";}}? >//1 2 4 5 6 7 8 9

Tip: Exit means pause the following program

Echo Date ("W");d ate in W for the day of the week < PHP header ("Content-type:text/html;charset=utf-8"), Echo date ("y-m-d"), or//Exit;echo "John" for the month and day respectively; >

Five. Remaining parts
1.do...while

<?php  $score =31;do{echo "



4.99 Multiplication Table
<?php for    ($i =1; $i <=9; $i + +) {for    ($j =1; $j <= $i; $j + +) {    echo "$i * $j =". $i * $j. " ";    }    echo "<br>";    }? >



3.PHP Implementation Calendar Table

Calendar table:
1. Two-layer for loop
2. Interlaced color change
3. Use the IF condition to judge
4.header Head Change Code
<?php  Header ("Content-type:text/html;charset=utf-8"); $days = 31;echo "<table width= ' 700px ' border= ' 1px ' > "for ($i =1, $i <= $days;) {echo" <tr> "; for ($j =0; $j <7; $j + +) {if ($i > $days) {echo" <td> </td > ";} Else{echo "<td>{$i}</td>";} $i + +;} echo "</tr>";} echo "</table>";? >

Add a background color

<?php  Header ("Content-type:text/html;charset=utf-8"); $days = 31;echo "<table width= ' 700px ' border= ' 1px ' > "for ($i =1; $i <= $days;) {$k ++;if ($k%2==1) {echo" <tr bgcolor= ' #cccccc ' > ";} Else{echo "<tr>";} for ($j =0; $j <7; $j + +) {if ($i > $days) {echo "<td> </td>";} else{echo "<td>{$i}</td>";} $i + +;} echo "</tr>";} echo "</table>";? > Abort Script 2.exit (); Abort script using    3.die ();    <?php  echo "11111<br>"; die ("Start script abort from here"); echo "2222222";? >


PHP class fifth automatic type conversion and Process Control