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I wanna put a default value on a textfield if _contact is not null. To do this
new TextField( decoration: new InputDecoration(labelText: "Email"), maxLines: 1, controller: new TextEditingController(text: (_contact != null) ? _contact.email: "")) Is there a better way to do that? E.g: Javascript would be something like: text: _contact ? _contact.email : ""
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Set a Variable's Value if it's Undefined using Ternary # Copied! A ternary operator is very similar to an if/else statement. If the condition ( myVar === undefined ) returns true , the value to the left of the colon is returned, otherwise the value to the right is returned.
The null coalescing operator is a useful feature of PHP that can be used as an alternative to the ternary operator and the isset() function. It is better than the ternary operator because it is faster and can check the values of multiple variables via chaining, as shown in the second example.
The conditional (ternary) operator is the only JavaScript operator that takes three operands: a condition followed by a question mark ( ? ), then an expression to execute if the condition is truthy followed by a colon ( : ), and finally the expression to execute if the condition is falsy.
Uses of Null Coalescing Operator: It is used to replace the ternary operator in conjunction with the PHP isset() function. It can be used to write shorter expressions. It reduces the complexity of the program. It does not throw any error even if the first operand does not exist.
Dart comes with ?. and ?? operator for null check.
You can do the following :
var result = _contact?.email ?? "" You can also do
if (t?.creationDate?.millisecond != null) { ... } Which in JS is equal to :
if (t && t.creationDate && t.creationDate.millisecond) { ... } If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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