When I upgrade from angular 8 to angular 9, I am getting a wired error saying that "Type 'string[]' is not assignable to type 'string'." when I run "npm install", below is the code that is getting this error.
let A = "";
if(error instanceof HttpErrorResponse){
...
}else{
B.fromError(error).then(errors => {
A = errors.splice(0, 5).map(function(re) {
return res.toString();
});
console.log(A);
}
It sounds odd to declare variable A as a string (initializing it to an empty string) and later in the else statement, you're assigning it a string array.
On the first line you declare A as an empty string:
let A = "";
Then you try to assign A the value of errors, which is an Array
A = errors.splice(0, 5).map(function(re) {
return res.toString();
});
You can't do that. Maybe replace the first line with:
let A: any[] = [];
Or replace any with whatever type the elements of errors are supposed to be.
Ais of typestringbecause that's what you initialise it as. Later on you're trying to assign an array of strings to it. That's where the type conflict comes from.