Method multiple

src/material/select/select.ts:441–443

()

  /** Whether the user should be allowed to select multiple options. */
  @Input({transform: booleanAttribute})
  get multiple(): boolean {
    return this._multiple;
  }
  set multiple(value: boolean) {
    if (this._selectionModel && (typeof ngDevMode === 'undefined' || ngDevMode)) {
      throw getMatSelectDynamicMultipleError();