Ternary Operator In Dart

Flutter Tutorial

Ternary Operator in Dart is an alternative way to control the logic flow like IF, else statement.
Ternary Conditional Operators are a pretty useful thing in Dart. They can be used to conditionally show a Flutter widget. They accept 2 operands.

The ternary operator takes three arguments, and it’s usually used when only two actions are needed. The ternary operator checks the first argument for comparison, the second is the action if the argument is true, and the third is the action if the argument is false.

For example

COMPARISON		True		False
isClosed	?	askToOpen()	:	askToClose()

Beginning Flutter

This will look familiar to you from the “Operators” section’s conditional expressions because it’s used often to make code flow decisions.

// Shorter way of if and else statement isClosed ? askToOpen() : askToClose();

Conditional chains

The ternary operator is right-associative, which means it can be “chained” to check multiple conditions in turn.

The syntax:

                     condition1 ? value1
                        : condition2 ? value2
                        : condition3 ? value3
                        : condition4 ? value4
                        : condition5 ? value5 // and so on
                        : valueN;

Example:

                     int mark = 70;
                     String result = mark > 80 ? 'A+'
                       : mark >70 ? 'A' 
                       : mark > 60 ? 'A-'
                       : mark >50 ? 'B'
                       : 'F';
                     print(result);

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