Simply use, array_merge() to concatenate two arrays in PHP. Let’s say the following are out arrays −$nameArray1 = array('John','David'); $nameArray2 = array('Mike','Sam');Now, set both the above arrays in array_merge() to concatenate them.The syntax is as follows −array_merge($yourFirstArrayName, $yourSecondArrayName);ExampleThe PHP code is as follows  Live Demo OutputThis will produce the following outputArray ( [0] => John [1] => David [2] => Mike [3] => Sam )

To check whether a string has no whitespace, use the preg_match() in PHP.The syntax is as follows preg_match('/\s/',$yourVariableName);ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputThe name (John Smith) has the space

For this, you can use the strtotime() method.The syntax is as follows −$anyVariableName= strtotime('anyDateValue + X minute');You can put the integer value in place of X.ExampleThe PHP code is as follows Live Demo OutputThis will produce the following output2020-10-30 10:15:20

Let’s say the following is our PHP array $listOfNames = array('John','David','Mike','David','Mike','David');We want the output to display the count of values in the above array like this −Array ( [John] => 1 [David] => 3 [Mike] => 2 )To get the count, use inbuilt function array_count_values().ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputArray ( [John] => 1 [David] => 3 [Mike] => 2 )

Let’s say the following is our string array −$full_name= '["John Doe","David Miller","Adam Smith"]';We want the output in a single string −John Doe, David Miller, Adam SmithFor this, use json_decode().ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputThe Result in one string=John Doe, David Miller, Adam Smith

For this, use $anyObjectName=new static() along with self.ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputJohn Doe

For random unique numbers array, use range() along with shuffle().ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputArray ( [0] => 11 [1] => 14 [2] => 15 [3] => 12 [4] => 18 )

You need to iterate using three for loops and lookup in given day, month and year. If the day, month and year is available, then put them into a variable.ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputThe next date value is =2018-05-25

Let’s say the following is our string with new line $sentence = " My name is John Smith My Favorite subject is PHP. ";We need to remove the new line above and replace with a whitespace i.e. the output should be −My name is John Smith My Favourite subject is PHP.For this, use trim() and withing that preg_replace() to replace.ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputMy name is John Smith My Favorite subject is PHP.

For this, use preg_split() along with array_shift() and array_pop(). Let’s say the following is our string with letters and numbers $values = "5j4o5h8n";We want to display the numbers and letters in separate arrays.ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputArray ( [0] => j [1] => o [2] => h [3] => n ) Array ( [0] => 5 [1] => 4 [2] => 5 [3] => 8 )