I have a method :
public cancelOperation(OperationId: string): Promise<void>
{
// some calls
}
I get OperationId from another method :
let operationId = GetOperationId() {}
which return nullable OperationId,
operationId?: string;
so when passing the OperationId received from GetOperationId(), I get error that operationId is nullable, so cant be used in method cancelOperation()
So is there any C# equivalent of
operationId .Value
or
operationId .HasValue
method in Typescript so I could go for it.
Though we have option to check operationId like :
cancelOperation(playAudioResult.operationId ? playAudioResult.operationId : "")
but I dont want to use it.
I need a solution which will something like : cancelOperation(operationId.?????)
if (operationId) will check for null in TypeScript.
It will return true if the value is not null or undefined.
You can use if to check whether the operationI is null or not. Tho other way is nullish coalescing operator.
It is a logical operator that returns its right-hand side operand when its left-hand side operand is null or undefined.
It carries out only if the value is not null like,
let x = operationI??NULL
Following the article shared by @ShamPooSham https://www.typescriptlang.org/docs/handbook/release-notes/typescript-2-0.html#non-null-assertion-operator
I got a way to get value from the nullable property as explained in the article.
We need to put ! after property and get the value(assuming that its not null)
// Compiled with --strictNullChecks
function validateEntity(e?: Entity) {
// Throw exception if e is null or invalid entity
}
function processEntity(e?: Entity) {
validateEntity(e);
let s = e!.name; // Assert that e is non-null and access name
}
Similary in my method I can use :
cancelOperation(playAudioResult.operationId!) // notice the !