Object 可能是 null。 TypeScript 错误（角度打字稿）

Question

I want to add an image file to "convert" function.

this is my code from the component.html for the input:

<li>
    <label for="avatarIMG" id="avatarLbL"> image: </label>
    <input type="file" accept="image/*" #imageBox name="image" id="avatarinput" (change)="convert($event)">
    <button type="button" id="avatarInputBTN" (click)="imageBox.click()"> Profile Picture </button>
</li>

the event suppose to send the values of the object with all of the values + the image file from the form to the component.ts and this is the code of it:

public convert(e: Event): void {
    this.eventFiles = (e.target as HTMLInputElement).files[0];
    if (this.eventFiles !== null) {
        this.user.image = this.eventFiles;
        const fileReader = new FileReader();
        fileReader.onload = args => this.preview = args.target?.result?.toString();
        fileReader.readAsDataURL(this.eventFiles);
    }
}

i get an error of object possibly null for (e.target as HTMLInputElement).files[0].

how can i fix this?..

Answer 1

try this:

this.eventFiles = (e.target as HTMLInputElement)?.files?.[0];