PHP lesson 5 automatic type conversion and process control _ PHP Tutorial

PHP class 5 automatic type conversion and process control. PHP fifth course automatic type conversion and process control Learning Overview: 1. learn about automatic type conversion 2. understand basic process control statements. 3. example: achieve automatic writing of calendar tables type PHP lesson 5 automatic type conversion and process control

Learning Overview:

1. learn about automatic type conversion

2. understand basic process control statements

3. example: compile a calendar table

Automatic type conversion

1) convert integer to string

echo $num."abc";

2) convert string to integer
$ Str + 3;
3) convert to Boolean type
False: 0 "" 0 "false array () null undefined


4) forced type conversion

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

5) constants

define("HOST","localhost");

6) operators
① RMB
++ --


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


③ Ternary
? :


Process control:
1. Process control
2. Functions




Process control:


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


II. loop control
For
While


3. abort a loop
Break: end directly

 ";}}?>//1 2

Continue: end this cycle

 ";}}?>//1 2 4 5 6 7 8 9

Tip: exit indicates that the following program is suspended.

Echo date ("w"); w in date indicates the day of the week
 

5. remaining parts
1. do... while

 =60);?>

4. multiplication table

 ";    }?>

3. implement calendar tables in PHP

Calendar table:
1. two-layer for loop
2. line-by-line color change
3. if condition judgment
4. encode the header

 ";for($i=1;$i<=$days;){echo "";for($j=0;$j<7;$j++){if($i>$days){echo " ";} else{echo "{$i}";}$i++;}echo "";}echo "";?>

Add background color

 "; For ($ I = 1; $ I <= $ days;) {$ k ++; if ($ k % 2 = 1) {echo"";} Else {echo"";}For ($ j = 0; $ j <7; $ j ++) {if ($ I >$ days) {echo" ";} Else {echo"{$ I}";}$ I ++;} echo"";} Echo"";?> Abort script 2. exit (); abort the script using 3.die ();
 "; Die (" Stop the script from here "); echo" 2222222 ";?>

And process control Learning Overview: 1. learn about automatic type conversion 2. learn about basic process control statements 3. example: implement automatic type writing for calendar tables...