Let’s understand the basic concept of functions.<\/p>\n\n\n\n
Defining a Function<\/h2>\n\n\n\n
A function can be defined by providing the name of the function with the appropriate parameter and return type. A function contains a set of statements which are called function body. The syntax is given below.<\/p>\n\n\n\n
Syntax:<\/strong><\/a><\/a><\/a><\/p>\n\n\n\n Let’s understand the general syntax of the defining function.<\/p>\n\n\n\n Let’s understand the following example.<\/p>\n\n\n\n Example – 1<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n After creating a function, we can call or invoke the defined function inside the\u00a0main() function\u00a0body. A function is invoked simply by its name with a parameter list, if any. The syntax is given below.<\/p>\n\n\n\n Syntax:<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n When we call a function, the control is transferred to the called function. Then the called function executes all defined statements and returns the result to the calling function. The control returns to the main() function..<\/p>\n\n\n\n Example :<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n When a function is called, it may have some information as per the function prototype is known as a parameter (argument). The number of parameters passed and data type while the function call must be matched with the number of parameters during function declaration. Otherwise, it will throw an error. Parameter passing is also optional, which means it is not compulsory to pass during function declaration. The parameter can be two types.<\/p>\n\n\n\n Actual Parameter –<\/strong> A parameter which is passed during a function definition is called the actual parameter.<\/p>\n\n\n\n Formal Parameter –<\/strong> A parameter which is passed during a function call is called the formal parameter.<\/p>\n\n\n\n We will learn more about the parameter in the next tutorial.<\/p>\n\n\n\n A function always returns some value as a result to the point where it is called. The return<\/strong> keyword is used to return a value. The return statement is optional. A function can have only one return statement. The syntax is given below.<\/p>\n\n\n\n Syntax:<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n Example –<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n Let’s understand the functions by using a program of adding two numbers using functions.<\/p>\n\n\n\n In the following example, we are creating a sum() function to add two number.<\/p>\n\n\n\n Example – 1<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n Output<\/strong><\/p>\n\n\n\n Explanation:<\/strong><\/p>\n\n\n\n In the above example, we declared a function named sum()<\/strong> and passed two integer variables as actual parameters. In the function body, we declared a result<\/strong> variable to store the sum of two numbers and returned the result.<\/p>\n\n\n\n In order to add two values, we called a function with the same name, passed formal parameters 30 and 20. The sum()<\/strong> returned a value which we stored in the variable c and printed the sum on the console.<\/p>\n\n\n\n As we discussed earlier, the parameters are optional to pass while defining a function. We can create a function without parameter return value. The syntax is given below.<\/p>\n\n\n\n Syntax:<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n Let’s understand the following example.<\/p>\n\n\n\n Example – 2<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n Output<\/strong><\/p>\n\n\n\n Explanation:<\/strong><\/p>\n\n\n\n In the above example, we created a function named greetings()<\/strong> without argument and returned the string value to the calling function. Then, we called the greeting() function inside the print statement and printed the result to the console.<\/p>\n\n\n\n We can declare a function without parameter and no return value. The syntax is given below.<\/p>\n\n\n\n Syntax:<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n In the above general syntax-<\/p>\n\n\n\n void –<\/strong> It represents the function has no return type.<\/p>\n\n\n\n fun_name –<\/strong> It represents the function name.<\/p>\n\n\n\n Let’s understand the following example.<\/p>\n\n\n\n Example – 3<\/strong><\/p>\n\n\n\n <\/a><\/a><\/a><\/p>\n\n\n\n Output<\/strong><\/p>\n\n\n\n Explanation:<\/strong><\/p>\n\n\n\n In the above example, we created a function called greeting()<\/strong> outside the main()<\/strong> function and writing the print statement. Inside the main()<\/strong> function, we called the defined function and printed the output to console.<\/p>\n\n\n\n We are creating a function to find the given number is even or odd. Let’s understand the following example.<\/p>\n\n\n\n Example – 4<\/strong><\/a><\/a><\/a><\/p>\n\n\n\n Output<\/strong><\/p>\n\n\n\n Dart function is a set of codes that together perform a specific task. It is used to break the large code into smaller modules and reuse it when needed. Functions make the program more readable and easy to debug. It improves the modular approach and enhances the code reusability. Suppose, we write a simple calculator […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[918],"tags":[],"_links":{"self":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/3610"}],"collection":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/comments?post=3610"}],"version-history":[{"count":0,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/3610\/revisions"}],"wp:attachment":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/media?parent=3610"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/categories?post=3610"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/tags?post=3610"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}return_type func_name (parameter_list): \n{ \n \/\/statement(s) \n return value; \n} <\/code><\/pre>\n\n\n\nint mul(int a, int b){ \n int c; \n c = a+b; \n print(\"The sum is:${c}\"); \n} <\/code><\/pre>\n\n\n\nCalling a Function<\/h2>\n\n\n\n
fun_name(<argument_list>); \nor \nvariable = function_name(argument); <\/code><\/pre>\n\n\n\nNote – Calling function must be ended with semicolon (;).<\/h4>\n\n\n\n
mul(10,20); <\/code><\/pre>\n\n\n\nPassing Arguments to Function<\/h2>\n\n\n\n
Return a Value from Function<\/h2>\n\n\n\n
![\"Dart](\"https:\/\/static.javatpoint.com\/tutorial\/dart\/images\/dart-function.png\")
<\/figure>\n\n\n\nreturn <expression\/values> <\/code><\/pre>\n\n\n\nreturn result; <\/code><\/pre>\n\n\n\nFunction Examples<\/h2>\n\n\n\n
Dart Function with parameter and return value<\/h3>\n\n\n\n
void main() { \n print(\"Example of add two number using the function\"); \n \/\/ Creating a Function \n \n int sum(int a, int b){ \n \/\/ function Body \n int result; \n result = a+b; \n return result; \n} \n\/\/ We are calling a function and storing a result in variable c \nvar c = sum(30,20); \nprint(\"The sum of two numbers is: ${c}\"); \n} <\/code><\/pre>\n\n\n\nExample of add two number using the function\nThe sum of two numbers is: 50\n<\/code><\/pre>\n\n\n\nDart Function with No Parameter and Return Value<\/h3>\n\n\n\n
return_type func_name() \n{ \n \/\/Statement(s); \n return value; \n} <\/code><\/pre>\n\n\n\nvoid main(){ \n\/\/ Creating a function without argument \nString greetings(){ \n return \"Welcome to Javapoint\"; \n} \n\/\/ Calling function inside print statement \nprint(greetings()); \n} <\/code><\/pre>\n\n\n\nWelcome to Javapoint\n<\/code><\/pre>\n\n\n\nDart Function with No Parameter and without a Return Value<\/h3>\n\n\n\n
func_name() { \n \/\/statement \n} \nOr \nvoid fun_name() { \n \/\/statement(s) \n} <\/code><\/pre>\n\n\n\n\/\/ Creating a function without argument \nvoid greetings() \n{ \n print(\"Welcome to JavaTpoint\"); \n} \nvoid main() { \n print(\"The example of Dart Function\"); \n \/\/ function callling \n greetings(); \n} <\/code><\/pre>\n\n\n\nThe example of Dart Function\nWelcome to JavaTpoint\n<\/code><\/pre>\n\n\n\nDart Function with Parameter and without a Return Value<\/h3>\n\n\n\n
void main() \n{ \n void number(int n){ \n \/\/ Check the given number is even or odd \n if (n%2 ==0){ \n print(\"The given number is even\"); \n } \n else { \n print(\"The given number is odd\"); \n } \n} \n number(20); \n} <\/code><\/pre>\n\n\n\nThe given number is even<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"