As someone new to Angular, I have a function in a component that makes API calls and expects results, but errors can also occur.
this.Service.callAPI().
.subscribe(data => {
if(data?.errors){
});
The issue is arising because both data and errors can be null. This results in a cannot read property of null error. How can I resolve this? I attempted using data?.errors?, but it did not work.
In HTML, the question mark is commonly utilized to verify if values are either undefined or null, whereas in TypeScript files, this functionality differs.
Instead of utilizing if(data?.errors), try using if(data && data.errors). This adjustment should resolve any issues.
We hope this solution resolves your problem efficiently.
To prevent null and undefined values, one method is to utilize the filter operator before subscribing.
Give this a try:
this.Service.callAPI().pipe(
filter(data => data !== undefined && data !== null),
).subscribe(data => {
if (data.errors) {
// now confirmed that data is not undefined or null
}
})
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