How to connect PHP sentences/Statements - php

When we are using HTML + PHP, say we want to output something like "Skill5" where "5" is load from php variable $number, we can do the following thing:
Skills<?php echo $number;?>
However, right now I want to do the same thing in PHP, I have a sentence like the following:
if($skills and $skills->skill5){
}
Where I want to load the number 5 from $variable $number too.
So I tried the following thing:
if($skills and $skills->skill.$number){
}
However, this is not working. this $number is working as "null" here even it's set to 5.
Any ideas?
Thank you very much!

Lets say $skills->skill = foo and $number = 5;
$skills->skill.$number
Would return foo5
Do it like this instead:
$pubVar = 'skill' . $number;
$skills->$pubVar
So you actually pull the skill5 public var.

Related

Issue Scraping with PHP

I am trying to attain a value, but step over other values that change dynamically.
The table section looks as follows:
Total 1.18 3.33 $20,000 16.2%
The code I am using to find the third value in preg_match is:
<?php
function get_total(){
$file_string = file_get_contents('url');
preg_match('#Total</td><td>\d\.\d+</td><td>d\.\d+</td><td>$(\d+)</td><td>d+\.\d\%\</td></tr></table><br><span id="ExStockDetailTableF1F2"#',$file_string, $data);
$loss = $data[1];
return $loss;
}
?>
Wouldn't it be easier just search for \$[\d\,]+ since represent third group?

Using Simple HTML DOM to extract an 'a' URL

I have this code for scraping team names from a table
$url = 'http://fantasy.premierleague.com/my-leagues/303/standings/';
$html = #file_get_html($url);
//Cut out the table
$FullTable = $html->find('table[class=ismStandingsTable]',0);
//get the text from the 3rd cell in the row
$teamname = $FullTable->find('td',2)->innertext;
echo $teamname;
This much works.. and gives this output....
Why Always Me?
But when I add these lines..
$teamdetails = $teamname->find('a')->href;
echo $teamdetails;
I get completely blank output.
Any idea why? I am trying to get the /entry/110291/event-history/33/ as one variable, and the Why Always Me? as another.
Instead do this:
$tdhtml = DOMDocument::loadHTML($teamdetails);
$link = $tdhtml->getElementsByTagName('a');
$url = $link->item(0)->attributes->getNamedItem('href')->nodeValue;
$teamdetails = $teamname->find('a')->href;
^^^^^^^^^---- never defined in your code
I also fail to see how your "works" code could possibly work. You don't define $teamname in there either, so all you'd never get is the output of a null/undefined variable, which is...no output all.
Marc B is right, I get that you don't have to initialize a variable, but he is saying you are trying to access a property of said variable:
$teamdetails = $teamname->find('a')->href;
^^^^^^^^^---- never defined in your code
This is essentially:
$teamname = null;
$teamname->find('a')->href;
The problem in your example is that $teamname is a string and you're treating it like a simple_html_dom_node

Calling php method from external function produces error

function KeepSamePage($text)
{
$sb_w = $oPdf->GetStringWidth($text);
$num_lines = explode("\n",$text);
$total = 0;
foreach($num_lines as $line)
{
$y = $oPdf->GetY();
$page_height = 11 * 25.4;
$this_width = $oPdf->GetStringWidth(strip_tags($line));
$extra_line = floor($this_width / $w);
$is_line = $this_width / ($w - 1);
$is_line = $this_width == 0 ? 1 + $extra_line : ceil($is_line) + $extra_line;
$total = $total + $is_line;
}
$sb_height = $total * 5;
if(($page_height - $y) < $sb_height){ $oPdf->AddPage(); }
}
KeepSamePage($signature_block);
I'm using FPDF and I'm creating a function to keep the signature page of a letter all on the same page. This checks to see if it would go to the next page and if soo, then it does an AddPage();
The issue I'm having is that when I don't have it in a function, it works perfectly, but when I put it within a function, I get errors when calling the methods in the class represented by $oPdf.
So, my question generally is this: Is it possible to have a regular function in PHP call a class method as I have below? If it is possible, what am I doing wrong?
ERROR GENERATED IS:
Fatal error: Call to a member function GetStringWidth() on a non-object in /home/jarodmo/public_html/cms/attorney_signature_block.php on line 18
Oh, and an explanation of my function just in case you're interested or someone else finds it.
Text has \n for new lines in it so the PDF will put the text of the signature block on the next line. Each new array element should be a new line, so I would need to multiply the number of lines by my line height, 5 in this case. (See $total * 5).
I check to see where we are on the page, find the difference between the page height and the Y position, then check that against the height of the signature block. If the signature block is bigger, then it wouldn't fit and I know we need a manual page break.
Also, because I do the explode with the \n to see the lines, I also have to check to make sure that none of the lines is still wider than the page otherwise it would word wrap and really be 2 lines (or more) where I was only counting it as 1 because it was just one array element. I know a signature block shouldn't have text wide enough to be on 2 lines, but I wrote this to be applicable for more than just signature blocks. I wanted to be able to call this function anywhere I wanted to make sure certain text stayed on the same page. Call the function, check the text I'm about to write to the PDF and move on knowing that the desired text would all be on the same page.
Thanks for all of the help and comments. SO is the best.
$oPdf
is not defined on your code. You need to define it, and maybe read PHP variable scope.
You are trying to access methods of the $oPdf object in your function, but your function has no idea what $oPdf is, thus, the error message.
you have to do something like this.
function KeepSamePage($text) {
$oPdf = new your_string_class();
$sb_w = $oPdf->GetStringWidth($text);
}
or
$oPdf = new your_string_class();
function KeepSamePage($text, $oPdf) {
$sb_w = $oPdf->GetStringWidth($text);
}
Try the following:
function KeepSamePage($text) {
global $oPdf;
…
}
The problem is, that the object is defined outside your function and you will have to allow your function to access it.
// Edit:
If you want to avoid global for whatever reason, you will have to pass your object to the function like this:
function KeepSamePage($text, $oPdf) {
…
// IMPORTANT! $oPdf has changed in this function, so you will have to give it back
return $oPdf;
}
You can call your function like this:
$oPdf = KeepSamePage($signature_block, $oPdf);
The advantage is, that you see in the main thread, that your function might has changed the object.
// Edit 2: I think, I was wrong on the edit1 in your case. As you pass the complete object to the function every change does apply to the object, so the changes will still be existant without giving back the result. If this was a variable that was defined in the main thread, you would have to give back the new value:
$a = 1;
function result1($a) {
++$a;
}
function result2($a) {
return ++$a;
}
echo $a."\n"; // 1
result1($a);
echo $a."\n"; // 1
$a = result2($a);
echo $a."\n"; // 2

PHP strange shuffle with require_once and array of strings

I hit a strange problem with PHP and its require_once language construct.
I require file called EN-en.php. It contains the English language for my website, I wrote it like this:
....
$lang['header']['loginbox']['menu'][1] = "contacts" ;
$lang['header']['loginbox']['menu'][2] = "settings" ;
....
Then I user this code to include my file in the whole site
require_once $langFile ;
Very easy I think, $langFile is = "/var/www/webstite/langs/EN-en.php". But here's come the strange part.
When I use
echo $lang['header']['loginbox']['menu'][1];
It prints something like "Gontacts" ... I can't understand why, and it's not the only case.. Please someone can help me with this issue?.
You are probably overwriting your own values in the array.
See this simple example:
$test = "some text";
$test['menu'] = 'extra';
var_dump($test);
// produces: string(9) "eome text"
// the first character - $test[0] - gets overwritten

Purpose of PHP parameters

I am trying to grasp the concept of PHP functions. I know how to create one.
function functionName()
{
//code to be executed;
}
I also know how to call a function. I am just a little confused as to what a parameter is for. I have read the php manual and w3schools.com's tutorial. From my understanding, you need a parameter to pass a value to the function? If that is correct why not just create it within the function? Why use a parameter?
Like this:
<?php
function num()
{
$s=14;
echo $s;
}
num();
?>
I know you can do:
<?php
function num($s=14)
{
echo $s;
}
num();
?>
or:
<?php
function num($s)
{
echo $s;
}
num($s=14);
?>
Could someone give me a real application of using a parameter, for say maybe a user based dynamic content website? I think it would help me understand it better.
Passing a parameter allows you to use one function numerous times. For example:
If you wanted to write ONE function that sent mail - you could pass the following parameters:
$to = $_POST['to'];
$from = $_POST['from'];
$subject = $_POST['subject'];
Then, in your function:
function sendmail($to, $from, $subject){
//code to be executed
}
Now you can reuse your send function at various points in your web app.
Here is an example, say you have numbers representing colors (this is common in storing data in a database) and you want to output what number represent's what color.
Say you had to do this a hundrend times for a hundred numbers.
You'd get pretty tired writing 100 if statments 100 times.
Here is a function example...
function colorType($type) {
if ($type == 1) {
return "Green";
}
elseif ($type == 2) {
return "Blue";
}
elseif ($type == 3) {
return "Red";
}
// etc
}
echo colorType(1) . "<br>"; // Green
echo colorType(2) . "<br>"; // Blue
echo colorType(3) . "<br>"; // Red
A function does something, and gives a result. It may accept parameters to arrive at that result, it may not. The simple calculator, as aforementioned, is a good one.
The easiest way to understand functions and parameters is to just read the PHP manual—most of the functions in the core PHP language take parameters of some sort. These functions are no different to the functions you write.
Let's assume you want to create a function that will allow people to sum numbers, you can't write needed variables in functions because you want others to input it and your function shows output:
function add($num1, $num2){
return $num1 + $num2;
}
Now anyone can call/use your function to sum numbers:
echo add(5,1); // 6
echo add(2,1); // 3
echo add(15,1); // 16
That's the most simplest example one can give to explain why you need parameters :)
When you specify function name($var=VALUE), you are setting a default.
function doit($s=14) {
return $s + 5;
}
doit(); // returns 19
doit(3); // returns 8
it makes your functions flexible to be reused in various situations, otherwise you would have to write many functions, one for each scenario. this is not only tedious, but becomes a nightmare if you have to fix something in those functions. instead of fixing it in one place, you would have to fix it in many places. you basically never want to have to copy paste code you have already written, instead you use arguments to make one set of the code flexible enough to handle each situation.
Paramaters allow your function to see the value of variables that exist outside of itself.
For example:
function F_to_C($temp) {
$temp = ($temp - 32) / 1.8;
return $temp;
}
$temperature = 32;
$new_temperature = F_to_C($temperature); // 0
echo $temperature;
$temperature2 = F_to_C(212); // 100
echo $temperature2;
Here we take $temperature, which we define in the code, but could be user input as from a form, and then send it to the function F_to_C. This allows us to convert it to Celsius, so we can then display it thereafter. In the next section, we then re-use the function to convert the boiling point, which is sent directly this time as the value 212. If we had embedded $temperature = 32 in the function the first time, then we would still get 0 as a result. However since we're using parameters, we instead get 100 back, because it's processing the value we specified when we invoked the function.

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