Lesson 2 php data types

Lesson 2 php data types

• 1.
  Welcome to Computer Programmer2 PHP Language – Lesson 2 Prepared By: Analyn G. Regaton
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  PHP Data Types Variablescan store data of different types, and different data types can do different things. PHP supports the following data types: •String •Integer •Float (floating point numbers - also called double) •Boolean •Array •Object •NULL •Resource
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  PHP String A stringis a sequence of characters, like "Hello world!". A string can be any text inside quotes. You can use single or double quotes:
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  PHP Integer An integerdata type is a non-decimal number between -2,147,483,648 and 2,147,483,647. Rules for integers: •An integer must have at least one digit •An integer must not have a decimal point •An integer can be either positive or negative •Integers can be specified in: decimal (base 10), hexadecimal (base 16), octal (base 8), or binary (base 2) notation In the following example $x is an integer. The PHP var_dump() function returns the data type and value:
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  PHP Float A float(floating point number) is a number with a decimal point or a number in exponential form. In the following example $x is a float. The PHP var_dump() function returns the data type and value:
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  PHP Boolean A Booleanrepresents two possible states: TRUE or FALSE. $x = true; $y = false; Booleans are often used in conditional testing. You will learn more about conditional testing in a later chapter of this tutorial.
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  PHP Array An arraystores multiple values in one single variable. In the following example $cars is an array. The PHP var_dump() function returns the data type and value:
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  PHP Object An objectis a data type which stores data and information on how to process that data. In PHP, an object must be explicitly declared. First we must declare a class of object. For this, we use the class keyword. A class is a structure that can contain properties and methods:
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  PHP NULL Value Nullis a special data type which can have only one value: NULL. A variable of data type NULL is a variable that has no value assigned to it. Tip: If a variable is created without a value, it is automatically assigned a value of NULL. Variables can also be emptied by setting the value to NULL:
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  PHP Resource The specialresource type is not an actual data type. It is the storing of a reference to functions and resources external to PHP. A common example of using the resource data type is a database call. We will not talk about the resource type here, since it is an advanced topic.
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  PHP String Functions strlen()- Return the Length of a String The PHP strlen() function returns the length of a string. In this chapter we will look at some commonly used functions to manipulate strings.
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  PHP String Functions str_word_count()- Count Words in a String The PHP str_word_count() function counts the number of words in a string.
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  PHP String Functions strrev()- Reverse a String The PHP strrev() function reverses a string.
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  PHP String Functions strpos()- Search For a Text Within a String The PHP strpos() function searches for a specific text within a string. If a match is found, the function returns the character position of the first match. If no match is found, it will return FALSE.
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  PHP String Functions strpos()- Search For a Text Within a String The PHP strpos() function searches for a specific text within a string. If a match is found, the function returns the character position of the first match. If no match is found, it will return FALSE. Tip: The first character position in a string is 0 (not 1).
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  PHP String Functions str_replace()- Replace Text Within a String The PHP str_replace() function replaces some characters with some other characters in a string.
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  The end !