Php set a Checkbox as checked at start from page

[Foracc]

Hello there,

I have a problem with the checkboxes. When the page is loaded A text file is to be evaluated. If the Line 2 = "Line 2"  then the checkbox from Checked should be marked

 

<?php


$Datei = file('test.txt')[2]; 


if(Datei = "Line 2"){

   //Here should be the Checkbox marked as Checked
 // should here come  the html code ?? <input type="checkbox" name="Checkbox" checked='checked' value="checkbox">Checkbox</input> 

 
    
}else{
    
       //Here should be the Checkbox as non Checked
  
    }
?>
<input type="checkbox" name="Checkbox" checked='checked' value="checkbox">Checkbox</input> 

 

Edited November 9, 2021 by Foracc

[ginerjm]

<input type="checkbox" name="Checkbox" checked value="true">Checkbox</input> 

All you need is 'checked' to set it.  Plus it is good to set a value such as 'true' or something indicative of which checkbox has been selected.  PS - in php I find it easier to use all lowercase names to avoid mis-types and wondering why something is not being recognized.  Remember - if a checkbox is not checked, then $_POST['Checkbox'] will not show up.

[Foracc]

32 minutes ago, ginerjm said:

<input type="checkbox" name="Checkbox" checked value="true">Checkbox</input> 

All you need is 'checked' to set it.  Plus it is good to set a value such as 'true' or something indicative of which checkbox has been selected.  PS - in php I find it easier to use all lowercase names to avoid mis-types and wondering why something is not being recognized.  Remember - if a checkbox is not checked, then $_POST['Checkbox'] will not show up.

 

hey thanks for the reply. Do I build the html into the PHP code? or can you change the HTML code via PHP?

[ginerjm]

You can send the html code from your php code and then use JS to check it from a trigger on your web page if you wish.  Need to set an id on the input tag to do that.

document.getElementById('chkbox').checked = true;

 

[Psycho]

In your if/then results, create a variable that will determine the checked status of the checkbox. I typically ise a ternary operator for these for brevity. Also, I would avoid using a name like "checkbox", give it a name as to what it is intended for.

$Datei = file('test.txt')[2]; 
$checkboxChecked = ($Datei == "Line 2") ? 'checked' : ''; //If true, set value to 'ckecked' else value is empty string
echo "<input type='checkbox' name='Checkbox' value='checkbox' {$checkboxChecked}>Checkbox</input>';

 

[Phi11W]

Or even something like this: 

$Datei = file('test.txt')[2]; 

printf( '<input type="checkbox" name="Checkbox" %s value="Y">Checkbox</input>' 
	, ( ( "Line 2" == Datei) ? 'checked' : '' ) 
	); 

"Danger, Will Robinson!"
Note my change to your "equality test" involving Datei: your original code would have "misbehaved" in interesting ways being, as it was originally given, an assignment! 

Regards, 
   Phill  W.