How to make a part of string variable bold

Question

Lets say I have a string variable goes like this:

$pro_details = 'Main Information: Goes Here';

Now I want to separate this variable into two pieces by the : sign. So one of the parts would be Main Information and the other part is Goes Here.

Then I want to make bold the 1st part Which is Main Information. So the output of this variable after this process would be:

Main Information: Goes Here

Till now I just know how to break down a variable like this:

$pro_details = explode(':', $row_results['pro_details']);

But I don't know how to make bold the first part just like I told you.

So, if you know how to solve this, please let me know.. thanks in advance!

===========================================================================

UPDATE 1:

Since I have 3 variables like the one I discussed about it here, I coded this:

 $pro_details1 = explode(':', $row_results['product_details1']);
 $pro_details1[0] = "<strong>{$pro_details1[0]}</strong>";
 $pro_details2 = explode(':', $row_results['product_details2']);
 $pro_details2[0] = "<strong>{$pro_details2[0]}</strong>";
 $pro_details3 = explode(':', $row_results['product_details3']);
 $pro_details3[0] = "<strong>{$pro_details3[0]}</strong>";

And I tried echoing them like this:

if (!empty($pro_details1)||(!empty($pro_details2))||(!empty($pro_details3))){
    echo "
        <p>
        <ul class='BHamid' style='font-size:25px;'>
    ";
    if(!empty($pro_details1)){
        echo "                                  
            <li>$pro_details1[0]:$pro_details1[1]</li>
        ";
    }
    if(!empty($pro_details2)){
        echo "
            <li>$pro_details2[0]:$pro_details2[1]</li>
        ";
    }
    if(!empty($pro_details3)){
        echo "
            <li>$pro_details3[0]:$pro_details3[1]</li>
        ";
    }
    echo "
        </ul>
        </p>
    ";
}

And then this error comes up:

Notice: Undefined offset: 1 on line 13

Line 13:

<li>$pro_details2[0]:$pro_details2[1]</li>

Because I set the 2nd pro_details (which is $pro_details2) empty in the table to see how this code works if one of the fields is empty.

So I need a way out of this error, because sometimes one of the pro_details variables can be NULL due to the project that I'm working on.

Answer 1

What about preg_replace:

$pro_details = 'Main Information: Goes Here';
echo preg_replace('/(.*):/', '<b>$1:</b>', $pro_details);

This captures everything before the colon and wraps it in tags.

Output:

<b>Main Information:</b> Goes Here

preg_replace uses regular expressions to search for patterns and to replace those patterns with something else. See the docs on the PHP site. preg_replace

Briefly:

The first arg is the search pattern. Books have been written on regular expressions so I won't go into it here other than to explain the example.

/(.*):/ means to search for a sequence of any character up to a colon ':'.

. means any character * means 0 or more of the preceding character.

The parens () are used to capture that sequence so it can be used in the replace side. The $1 in the second parameter is the sequence of characters that was found inside the parens in the search parameter.

If I wrote this in English, it would read as follows: Find a sequence of characters up to but not including a colon. Replace that sequence of characters by prefixing <b> and suffixing </b>, leaving the rest of the string unmodified.

One other thing to note. In this specific case, we could actually use str_replace() because we know the opening bold tag goes at the beginning.

echo '<b>' . str_replace(':', ':</b>', $pro_details);

Answer 2

Explode on the colon just like you said...

 $pro_details = explode(':', $row_results['pro_details']);

Then wrap the first one in a <b> tag which makes it bold when rendered in the broswer.

$pro_details[0] = "<b>{$pro_details[0]}</b>";

Then implode them again.

$pro_details = implode(':', $pro_details);

And there you go... echo $pro_details;

---

I would make a function so you're not repeating yourself so much.

function boldifyTitle($pd){
    $pd = explode(':', $pd);
    $pd[0] = "<b>$pd</b>";
    if(empty($pd[1])) $pd[1] = "";
    return implode(':', $pd);
}

echo "<li>".boldifyTitle($pro_details[0])."</li>";