A PHP nested if statement is optimized

The if statement is still very fast to execute, and it doesn't need to be optimized.

Use ** indentation to distinguish the nested hierarchy of if statements.

Use the tooltip information to distinguish braces pairing information.

Use the folding function of the device to fold up the irrelevant logic and highlight the if level.

{} inside is an independent statement, which has nothing to do with the outside, and you can also write a string of judgments like you do, for example:

1. Just look at the program in your second picture, you should have also run it, no problem, but is numeric is to detect whether the variable is a number or a string of numbers, for example:'12345'with'', all correct, you have to know this;

2. Let's take a look at the program on your first picture:

1) Your first judgment if($theif=0) is not right, = represents the assignment rather than the judgment, it should be if($theif==0), or you can directly if($theif), because 1 and 0 represent true and false respectively when judging.

2) Your second judgment isset(), this function is to determine whether the variable exists, why it needs to be output if it already exists"It can't be empty"？Should be! isset()。

The above is an interpretation of your program, you can make a few more breakpoint output judgments in the program, which will help you know the problem of the program faster.

I like the logical structure below, FYI:

errstr = "";Error messages.

outstr = "";Execution result.

if ($in_deport=='') $errstr .= "Error 1";

if ($out_deport=='') $errstr .= "Mistake 2";

if ($in_deport==out_deport) $errstr .= "Error 3";

if ($errstr==''){

sql='..';

if (!res) $errstr .= "Error 4";

if ($errstr==''){

sql='..';

if (.errstr .= "Mistake 5: Insufficient inventory";

if ($errstr==''){

sql='..';

if (.errstr .= "Mistake 6: It doesn't exist";

if ($errstr==''){

sql='..';

if (.errstr .= "Error 7: Failed to write to the database";

else $outstr .= "The data was written to the database successfully";

echo<<$errstr

outstr

end;

If an exception occurs earlier, you should return the operation directly. For example, do the prompt if(!).$res)

sql = "Check that the product is in stock enough";

res1 = '';

if(!$res1)

sql = "Check if the product is in the warehouse";

res2 = '';

if(!$res2)

else

With the associated array, as follows:

arr = array(

1"=>"30",2"=>"10",3"=>"57",4"=>"99",5"=>"80",6"=>"97",7"=>"135",8"=>"40",;$sz += $arr[$sum];

Concentrate the parts that will change in the associated array $arr, and then maintain and change, just change the $arr array.

Using PHP nested ifesle implementation, here's an example that will solve your problem.

get['a'];Here, get the get value of the version and change it to your get session

echoa;if($a

0)else