Updating an image in Angular 6

I am currently working with Angular 6 and Firebase. I am looking to update an image on the server.

Here is a snippet of my HTML:

<div class="form-check">
    <input type="file" (change)="onFileSelected($event)">
  </div>

This is the variable I am using: selectedFile = null;

Below is the method in my component:

 onFileSelected(event) {

this.selectedFile = event.target.file[0];

}

I encountered this error message:

ERROR TypeError: Cannot read property '0' of undefined

Does anyone know why this error is occurring?

angulartypescript

Answer №1

handleFileUpload(event) {
    this.uploadedFile = event && event.target.files.length > 0 ? event.target.files[0] : '';
}

const formData: FormData = new FormData();
formData.append('file', this.uploadedFile);
let reqHeaders = new HttpHeaders();
reqHeaders = reqHeaders.delete('Content-Type');
const uploadUrl = `api/upload`
this.httpClient.post(uploadUrl, formData, { headers: reqHeaders });

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