Getting Started with Dart

2022-11-07

Dart Introduction

it is optimized programming language developed by google used to develop mobile and desktop application.

1. Flutter uses dart language to develop application
2. Dart language is C-type Programming language.
3. Used to develop single page application
4. extension is .dart

Dart syntax

	
	main(){
    print("hello");
		// this is single line comment
		/*
		 this is
		 multiline comments
		*/
}
	
	

Dart data-type

1. Number - int, double
2. String - 
3. Boolen

Dart data-type conversion

1. String to int :- int.parse("string");
2. String to double : double.parse("string");
3. Int to String : int_val.toString();

To know the data-type of variable : var_name.runTimeType

String Interpolation

1.  Concatination : + is used to concatinate 
2. Interpolation : ${expression}  is used to write expression in between of double quote inside print statement.
3. $ : $varname is used to display variable content in between of double quote inside print. 

var Keyword

• var keyword is used to define variable without specifying it's type.
• value can be changed by datatype can't 

Dynamic keyword

• it is also used to define variable.
• value and data-type both can be changed.

if else, loop and function

main(){
// if else
if( 4 > 2 ){
// true block
}else{
 // false block
}

// for loop
for(var i = 0; i < 5; i++){
 print(i);
}

// while loop
var j = 4;
while( j < 10 ){
print(j);
j++;
}

// calling function
disp();
}

// defining function
void disp(){
 print("hi");
}




OOP Concept

class abc{

void disp(){
 print("hi");
}

}


main(){
  abc x = abc();//crearing object 
	x.disp(); // calling function
}