PHP Developer’s Dictionary IT-SC book 185 The trim() function removes whitespace from str and returns the resulting string. Whitespace includes "\\ n" , "\\ r" , "\\ t" , "\\ v" , "\\ 0" , and a plain space. ucfirst Syntax string ucfirst(string str) Description The ucfirst() function capitalizes the first character of str if it is alphabetic. The alphabet is determined by the current locale setting. $text = "hello world!"; echo ucfirst($text);//displays Hello world! ucwords() Syntax string ucwords(string str) Description The ucwords() function, which was added in PHP 3.0.3 and PHP 4.0, returns a string that is str with each word's first letter uppercased if it is alphabetic. $text = "hello world!"; echo ucwords($text);//displays Hello World! Variable The following functions deal primarily with getting and setting variable types. doubleval() Syntax double doubleval(mixed var) PHP Developer’s Dictionary IT-SC book 186 Description The doubleval() function returns the double (floating-point) value of the var parameter. The var parameter must be a scalar type and not an object or array. empty() Syntax int empty(mixed var) Description The empty() function determines whether a variable is set. It returns false if var is set to a nonempty or nonzero value, and true otherwise. gettype() Syntax string gettype(mixed var) Description The gettype() function returns the PHP-defined type of the parameter var . Possible PHP types include integer, double, string, array, object, and unknown type. $avar = array(1,2,3); echo gettype($avar);//displays array intval() Syntax int intval(mixed var, int [base]) Description PHP Developer’s Dictionary IT-SC book 187 The intval() function returns the integer value of the parameter var using the specified base for the conversion. base is an optional parameter with 10 as the default. The parameter var may be any scalar type. Note that you cannot use intval() on arrays or objects. echo (intval("123"));//displays 123 echo (intval("10",16));//displays 16 is_array() Syntax int is_array(mixed var) Description The is_array() function returns true if var is an array and returns false otherwise. is_boolean() Syntax int is_bool(mixed var ) Description The is_bool() function, which was added in PHP 4.0b4, returns true if var is a Boolean value and returns false otherwise. is_double() Syntax int is_double(mixed var) Description The is_double() function returns true if var is a double and returns false otherwise. PHP Developer’s Dictionary IT-SC book 188 is_float() Syntax int is_float(mixed var ) Description The is_float() function returns true if var is a double and returns false otherwise. This function is an alias for is_double(). is_int() Syntax int is_int(mixed var) Description The is_int() function returns true if var is an integer (long) and returns false otherwise. This function is an alias for is_long() . is_integer() Syntax int is_integer(mixed var) Description The is_integer() function returns true if var is an integer ( long) and returns false otherwise. This function is an alias for is_long() . is_long() Syntax int is_long(mixed var) PHP Developer’s Dictionary IT-SC book 189 Description The is_long() function returns true if var is an integer (long) and returns false otherwise. is_numeric() Syntax int is_numeric(mixed var) Description The is_numeric() function, which was added in PHP 4.0RC1, returns true if var is a number or a numeric string and returns false otherwise. is_object() Syntax int is_object(mixed var) Description The is_object() function returns true if var is an object and returns false otherwise. is_real() Syntax int is_real(mixed var) Description The is_real() function returns true if var is a double, and returns false otherwise. This function is an alias for is_double(). is_string() Syntax . string ucwords(string str) Description The ucwords() function, which was added in PHP 3.0.3 and PHP 4.0, returns a string that is str with each word's first letter uppercased if. gettype(mixed var) Description The gettype() function returns the PHP- defined type of the parameter var . Possible PHP types include integer, double, string, array, object, and unknown type with getting and setting variable types. doubleval() Syntax double doubleval(mixed var) PHP Developer’s Dictionary IT-SC book 186 Description The doubleval() function returns the double