Getting Started with dart-control processes and other

Introduction to dart-control processes and other control processes If~else

If statement and optional Else statement, a simple if statement can be handled with the conditional operator (?:)

if{    you.bringRainCoat();}elseif{    you.wearJacket();}else{    car.putTopDown();}

For

Iterating using a For loop

varnew StringBuffer("Dart is fun");for (var05; i++) {    message.write(‘!‘);}

Iterating over a iteration object using the foreach () method

List<String> names = ["Alice""Daphne""Elizabeth""Joanna"];names.forEach((name){    print(name);});

Use For~in to iterate through the list type and set type of the Iteration object

var collection = [012];for (varin collection) {  print(x);}

While, Do~while

While loop, first judge the condition and then enter the loop.

while (!isDone()) {    doSomething();}

Do~while cycle, first enter the cycle and then judge the condition

do {    while (!atEndOfPage());

Break, continue

Stop a loop with break

while (true) {    ifbreak;    processIncomingRequest();}

Skip this cycle with continue

fori0;icandidates.length;i{    var candidate = candidates[i];    if (candidate.yearsExperince < 5) {        continue;    }    candidate.interview();}

Switch, case

Switch is typically used for the comparison of integers, strings, and compile constants, and the objects must be of the same type, each case must end with a break

varCommand =' OPEN ';Switch(command) { Case ' CLOSED ': executeclosed (); Break; Case ' PENDING ': Executepending (); Break; Case ' approved ': Executeapproved (); Break; Case ' DENIED ': Executedenied (); Break; Case ' OPEN ': Executeopen (); Break;default: Executeunknown (); }

Can fail if case content is empty, or use continue to continue execution

var‘CLOSED‘;switch (command) {    case‘CLOSED‘:        executeClosed();        continue nowClosed;nowClosed:    case‘NOW_CLOSED‘:        executeNowClosed();        break;}

Assert

Use an Assert statement to disturb normal operation if the Boolean value is False, only in check mode

//确保变量非空assertnull);//确保值小于100assert100);//确保这是一个https URLassert(urlString.startsWith(‘https‘));

Comments

// 这是一行注释/*    这是一大段注释*/

private variables and functions

There are no public, protected, and private keywords in dart syntax, so you can declare a private variable or function simply by adding "_" in front of the identifier.

Add content at irregular intervals

Getting Started with dart-control processes and other