concatenation assignment operator php

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Assignment Operators

The basic assignment operator is "=". Your first inclination might be to think of this as "equal to". Don't. It really means that the left operand gets set to the value of the expression on the right (that is, "gets set to").

The value of an assignment expression is the value assigned. That is, the value of " $a = 3 " is 3. This allows you to do some tricky things: <?php $a = ( $b = 4 ) + 5 ; // $a is equal to 9 now, and $b has been set to 4. ?>

In addition to the basic assignment operator, there are "combined operators" for all of the binary arithmetic , array union and string operators that allow you to use a value in an expression and then set its value to the result of that expression. For example: <?php $a = 3 ; $a += 5 ; // sets $a to 8, as if we had said: $a = $a + 5; $b = "Hello " ; $b .= "There!" ; // sets $b to "Hello There!", just like $b = $b . "There!"; ?>

Note that the assignment copies the original variable to the new one (assignment by value), so changes to one will not affect the other. This may also have relevance if you need to copy something like a large array inside a tight loop.

An exception to the usual assignment by value behaviour within PHP occurs with object s, which are assigned by reference. Objects may be explicitly copied via the clone keyword.

Assignment by Reference

Assignment by reference is also supported, using the " $var = &$othervar; " syntax. Assignment by reference means that both variables end up pointing at the same data, and nothing is copied anywhere.

Example #1 Assigning by reference

The new operator returns a reference automatically, as such assigning the result of new by reference is an error.

The above example will output:

More information on references and their potential uses can be found in the References Explained section of the manual.

Arithmetic Assignment Operators

Bitwise Assignment Operators

Other Assignment Operators

• arithmetic operators
• bitwise operators
• null coalescing operator

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There are two string operators. The first is the concatenation operator (‘ . ‘), which returns the concatenation of its right and left arguments. The second is the concatenating assignment operator (‘ .= ‘), which appends the argument on the right side to the argument on the left side. 

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Home » PHP Tutorial » PHP Assignment Operators

PHP Assignment Operators

Summary : in this tutorial, you will learn about the most commonly used PHP assignment operators.

Introduction to the PHP assignment operator

PHP uses the = to represent the assignment operator. The following shows the syntax of the assignment operator:

On the left side of the assignment operator ( = ) is a variable to which you want to assign a value. And on the right side of the assignment operator ( = ) is a value or an expression.

When evaluating the assignment operator ( = ), PHP evaluates the expression on the right side first and assigns the result to the variable on the left side. For example:

In this example, we assigned 10 to $x, 20 to $y, and the sum of $x and $y to $total.

The assignment expression returns a value assigned, which is the result of the expression in this case:

It means that you can use multiple assignment operators in a single statement like this:

In this case, PHP evaluates the right-most expression first:

The variable $y is 20 .

The assignment expression $y = 20 returns 20 so PHP assigns 20 to $x . After the assignments, both $x and $y equal 20.

Arithmetic assignment operators

Sometimes, you want to increase a variable by a specific value. For example:

How it works.

• First, $counter is set to 1 .
• Then, increase the $counter by 1 and assign the result to the $counter .

After the assignments, the value of $counter is 2 .

PHP provides the arithmetic assignment operator += that can do the same but with a shorter code. For example:

The expression $counter += 1 is equivalent to the expression $counter = $counter + 1 .

Besides the += operator, PHP provides other arithmetic assignment operators. The following table illustrates all the arithmetic assignment operators:

Concatenation assignment operator

PHP uses the concatenation operator (.) to concatenate two strings. For example:

By using the concatenation assignment operator you can concatenate two strings and assigns the result string to a variable. For example:

• Use PHP assignment operator ( = ) to assign a value to a variable. The assignment expression returns the value assigned.
• Use arithmetic assignment operators to carry arithmetic operations and assign at the same time.
• Use concatenation assignment operator ( .= )to concatenate strings and assign the result to a variable in a single statement.

• PHP String Operators

In PHP, string operators, such as the concatenation operator (.) and its assignment variant (.=), are employed for manipulating and concatenating strings in PHP. This entails combining two or more strings. The concatenation assignment operator (.=) is particularly useful for appending the right operand to the left operand.

Let’s explore these operators in more detail:

Concatenation Operator (.)

The concatenation operator (.) is utilized to combine two strings. Here’s an example:

You can concatenate more than two strings by chaining multiple concatenation operations.

Let’s take a look at another pattern of the concatenation operator, specifically the concatenation assignment operator.

Concatenation Assignment Operator (.=)

The .= operator is a shorthand assignment operator that concatenates the right operand to the left operand and assigns the result to the left operand. This is particularly useful for building strings incrementally:

This is equivalent to $greeting = $greeting . " World!"; .

Let’s see some examples

Examples of Concatenating Strings in PHP

Here are some more advanced examples demonstrating the use of both the concatenation operator (.) and the concatenation assignment operator (.=) in PHP:

Concatenation Operator ( . ):

In this example, the . operator is used to concatenate multiple strings and variables into a single string.

Concatenation Assignment Operator ( .=) :

Here, the .= operator is used to append additional text to the existing string in the $paragraph variable. It is a convenient way to build up a string gradually.

Concatenation Within Iterations:

You can also use concatenation within iterations to build strings dynamically. Here’s an example using a loop to concatenate numbers from 1 to 5:

In this example, the .= operator is used within the for loop to concatenate the current number and a string to the existing $result string. The loop iterates from 1 to 5, building the final string. The rtrim function is then used to remove the trailing comma and space.

You can adapt this concept to various scenarios where you need to dynamically build strings within loops, such as constructing lists, sentences, or any other formatted output.

These examples showcase how you can use string concatenation operators in PHP to create more complex strings by combining variables, literals, iterations and other strings.

Let’s summarize it.

Wrapping Up

PHP provides powerful string operators that are essential for manipulating and concatenating strings. The primary concatenation operator (.) allows for the seamless combination of strings, while the concatenation assignment operator (.=) provides a convenient means of appending content to existing strings.

This versatility is demonstrated through various examples, including simple concatenation operations, the use of concatenation assignment for gradual string construction, and dynamic string building within iterations.

For more PHP tutorials, visit here or visit PHP Manual .

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• How to Concatenate Strings in PHP

Use the Concatenation Operator to Concatenation Strings in PHP

Use the concatenation assignment operator to concatenate strings in php, use the sprintf() function to concatenate strings in php.

This article will introduce different methods to perform string concatenation in PHP.

The process of joining two strings together is called the concatenation process. In PHP, we can achieve this by using the concatenation operator. The concatenation operator is . . The correct syntax to use this operator is as follows.

The details of these variables are as follows.

The program below shows how we can use the concatenation operator to combine two strings.

Likewise, we can use this operator to combine multiple strings.

In PHP, we can also use the concatenation assignment operator to concatenate strings. The concatenation assignment operator is .= . The difference between .= and . is that the concatenation assignment operator .= appends the string on the right side. The correct syntax to use this operator is as follows.

The program below shows how we can use the concatenation assignment operator to combine two strings.

In PHP, we can also use the sprintf() function to concatenate strings. This function gives several formatting patterns to format strings. We can use this formatting to combine two strings. The correct syntax to use this function is as follows.

The function sprintf() accepts N+1 parameters. The detail of its parameters is as follows.

The function returns the formatted string. We will use the format %s %s to combine two strings. The program that combines two strings is as follows:

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Concatenate Strings in PHP

Php examples tutorial index.

Concatenating strings is a crucial concept in PHP that enables developers to merge two or more strings to create a single string. Understanding how to concatenate strings efficiently is vital in generating dynamic content, creating queries, and managing data output. In this tutorial, you will learn how to concatenate strings in PHP.

Understanding String Concatenation in PHP

String concatenation refers to joining two or more strings to create a new string. It is a typical and helpful operation in PHP, allowing developers to create customized and dynamic strings by combining different sources. The dot ( . ) operator performs this operation in PHP by joining the strings and creating a new string. This feature is simple and efficient and is commonly used in PHP scripting.

Basic Concatenation with the Dot Operator

The easiest and most common way to concatenate strings in PHP is to use the dot ( . ) operator. The dot operator takes two operands (the strings to be concatenated) and returns a new string as the result of concatenating them.

In the above example, we combine two variables ( $firstName and $lastName ) with a space between them to form a full name.

Concatenation with Assignment Operator

PHP makes string manipulation easier with the concatenation assignment operator ( .= ). This operator appends the right-side argument to the left-side argument, making it simple to expand an existing string.

The above method simplifies how to efficiently append text to an existing string variable, enhancing its content without redundancy.

Concatenating Multiple Variables and Strings

You can concatenate multiple variables and strings using multiple dot operators in a single statement. It is beneficial when you need to create a sentence or message from different data sources:

Dynamic Content Creation

String concatenation helps generate dynamic content and allows tailored user experiences based on specific inputs or conditions.

The above example illustrates how to create a personalized greeting message using concatenation dynamically.

In this tutorial, you have learned about the process of string concatenation in PHP, how to use the dot and assignment operators to join strings together, and some examples of string concatenation in PHP for different purposes. String concatenation is a crucial aspect of managing dynamic content and data output. Applying the best practices and techniques outlined in this tutorial, you can efficiently use string concatenation in your PHP projects.

String Operators in PHP : Tutorial

Concatenation Operator

Concatenation assignment operator (.=).

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PHP » Operators » .=

Concatenation assignment operator.

Concatenates the left operand and the right operand.

Explanation:

A variable is changed with an assignment operator.

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Concatenating Strings in PHP

What is php.

PHP , an open-source scripting language widely used for web development, can be integrated into HTML code, where PHP and HTML syntax constructs can be mixed in one file. PHP is known for its flexibility and large developer community. PHP supports multiple databases such as MySQL , PostgreSQL , and SQLite . PHP can run on many operating systems, including Windows, Linux, and macOS.

What is a string in PHP?

In PHP , a string is a sequence of characters, representing each character by a byte. Due to the limited range of a byte (256 characters), PHP strings do not support Unicode strings. However, PHP offers several ways to work with Unicode strings. You can create PHP strings using single quotes ('...'), double quotes ("..."), and Heredoc syntax (<<<). PHP provides many built-in string functions for various operations such as comparison , replacement , interpolation , splitting , etc.

PHP Concatenate Strings Examples

The following are examples of string concatenation in PHP:

Concatenating strings using concatenate operator (' . ')

To concatenate strings in PHP, you can use the concatenation operator (' . '), which will concatenate the strings and assign the result to a variable.

Concatenating strings using the assignment operator (' .= ')

To concatenate strings, you can aloso use the concatenation assignment operator (' .= '), which adds the argument on the right side to the argument on the left side.

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PHP 101: Concatenating Assignment Operator

Lab: wordpress custom taxonomy basics.

Video Runtime: 02:26

The term “concatenating” means that we are smooshing two strings together by appending the one on the right to the one on the left. The result is a new string value.

For example, let’s say that a variable $post_meta has a value of '[post_categories] [post_tags]' . You want to append another shortcode to the end of it. How do you do that?

There are two different ways to achieve this and make an assignment.

Long Hand Approach

To concatenate an existing variable’s string value to some value you are processing, you have a couple of choices in PHP. You can do it with the long hand approach, like this:

$post_meta = $post_meta . ' [post_terms taxonomy="department"]';

where the shortcode’s string literal is smooshed together to the end of the string value in the variable $post_meta . Then the new string is assigned back to the variable. That’s the long hand version.

Short Hand Approach

PHP provides you with a concatenating assignment operator as a shorthand approach:

$post_meta .= ‘ [post_terms taxonomy=”department”]’;

This code works the same as the full version; however, it’s more condensed. It eliminates the repetitious repeating of the variable. Therefore, this approach is more readable and maintainable.

This approach is very popular and prevalent! Make sure you understand it completely!

What’s the Sequence and Result?

Let’s walk through the processing and look at the result.

Step 1: Concatenate

First the variable’s value and string literal are concatenated to form a new string value of:

'[post_categories] [post_tags] [post_terms taxonomy="department"]';

Step 2: Assignment

The next step is to assign the new string to the variable $post_meta , which means the value it represents is changed to:

$post_meta = '[post_categories] [post_tags] [post_terms taxonomy="department"]';

This Episode

In this episode, let’s talk about the process of concatenating. Then we’ll walk through how each of these approaches works. Finally, we’ll see the results.

Code Challenge

Let’s challenge you. Ready? When this function is called, a string literal of '[post_categories]' is passed to it and assigned to the parameter $html . What is the value returned when the function is done running?

Answer : '[post_categories] [post_terms taxonomy="department"]'

Why? PHP concatenates the incoming value with the string literal and then assigns it back to the variable. Then that variable’s value is returned.

Did you get it right? If yes, way to go!! If no, watch the video and if it still doesn’t make sense, come ask me in the Pro Forums.

You get WET when you swim. Stay DRY when you code.

Total Lab Runtime: 01:30:53

• 1 Lab Introduction free 08:15
• 2 Custom Taxonomy - The What, Why, and When free 08:32
• 3 Registering a Custom Taxonomy pro 09:54
• 4 Configure the Labels pro 14:51
• 5 Bind to Post Types pro 11:55
• 6 Configuring Arguments pro 07:52
• 7 Render Entry Footer Terms pro 08:40
• 8 PHP 101: Concatenating Assignment Operator pro 02:26
• 9 PHP 101: Building Strings pro 08:19
• 10 Test Entry Footer Terms pro 03:03
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PHP: String operator

There are two string operators : concatenation operator ('.') and concatenating assignment operator ('.=').

Example : PHP string concatenation operator

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Example: PHP string concatenating assignment operator

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Operators are used to perform operations on variables and values.

PHP divides the operators in the following groups:

• Arithmetic operators
• Assignment operators
• Comparison operators
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• Logical operators
• String operators
• Array operators
• Conditional assignment operators

PHP Arithmetic Operators

The PHP arithmetic operators are used with numeric values to perform common arithmetical operations, such as addition, subtraction, multiplication etc.

PHP Assignment Operators

The PHP assignment operators are used with numeric values to write a value to a variable.

The basic assignment operator in PHP is "=". It means that the left operand gets set to the value of the assignment expression on the right.

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PHP Comparison Operators

The PHP comparison operators are used to compare two values (number or string):

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The PHP increment operators are used to increment a variable's value.

The PHP decrement operators are used to decrement a variable's value.

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The PHP logical operators are used to combine conditional statements.

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PHP has two operators that are specially designed for strings.

PHP Array Operators

The PHP array operators are used to compare arrays.

PHP Conditional Assignment Operators

The PHP conditional assignment operators are used to set a value depending on conditions:

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Concatante PHP variables inside loop by a "Concatenating Assignment Operator", and Echo each output loop separately

With the "Concatenating Assignment Operator" I assigned in the loop two variables. I need to get each loop result separately. The problem is that I don't know why each next loop result is copied to each next loop result.

Using this code, I get the output:

I'm working on making the output look like this:

• 7 You need to reset $output at the top of the loop. –  aynber Commented Dec 1, 2021 at 14:14

You are always concatenating values to the $output, you never clear it, so the numbers are just continually added. All you need to do is change the first $output .= "1"; in to a $output = "1"; and that will have the effect of resetting $output to the one character ready to be concatenated with the second.

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