# AUR0903

### **Error message**

Invalid Dialog Settings. You must provide either "component" or "template" or both.

### **Parameters**

None

### Error explanation

This error occurs when you attempt to open a dialog using `IDialogService.open()` without providing either a `component` or a `template` in the settings object. At least one of these is required to define the content of the dialog.

### Common causes

* Calling `dialogService.open({})` with an empty settings object.
* Providing a settings object that omits both `component` and `template`.
* Dynamically creating the settings object and failing to include `component` or `template`.

### How to fix

* Ensure your dialog settings object includes at least one of the following properties:

  * `component`: A function returning a component constructor, instance, or promise thereof.
  * `template`: A string, HTML element, or a function returning a string, HTML element, or promise thereof.

  ```typescript
  // Example using component
  dialogService.open({ component: () => MyDialogComponent });

  // Example using template
  dialogService.open({ template: '<div>My Dialog Content</div>' });

  // Example using both
  dialogService.open({ component: () => MyDialogViewModel, template: myDialogTemplate });
  ```

### Debugging tips

* Check the settings object being passed to `dialogService.open()`.
* Verify that the `component` or `template` property is present and correctly defined.
* Use the browser debugger to inspect the settings object just before `dialogService.open()` is called.


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