ngx-lower-case-directive
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This directive helps to convert an input text value to lower case.
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# Angular Lower Case Directive
This directive helps to convert an input text value to lower case.
It lies on a simple fact that *Angular listens to `input` event to bring the view-to-model binding into being*.
_* According to the description of [updateOn property of AbstractControlOptions interface](https://angular.io/api/forms/AbstractControlOptions), when updateOn is set to `blur` or `submit`, Angular listens to `blur` or `submit` event for model update. In this directive, `update-on-blur` case is handled in a hack way. No further processing is required for `update-on-submit` case._
Since extra `input` and `blur` events are dispatched, if you bind a callback to `input` event or `blur` event, the callback will be invoked twice on `input` or `blur`.
To overcome the disadvantage, a debounced function is recommended for the event binding.
The directive works with Angular 5 and 6. To use it in Angular 4, you may import the .ts file directly (see *Usage*). For Angular 2, you may try it in Angular 4's way, but it's not tested.
## Usage
1.Install `ngx-lower-case-directive`.
```bash
npm i -S ngx-lower-case-directive
```
2.Import `NgxLowerCaseDirectiveModule` to your Angular module.
**Angular 4**
```typescript
import { NgxLowerCaseDirectiveModule } from 'ngx-lower-case-directive/src';
@NgModule({
imports: [
...
NgxLowerCaseDirectiveModule,
...
],
...
```
**Angular 5+**
```typescript
import { NgxLowerCaseDirectiveModule } from 'ngx-lower-case-directive';
@NgModule({
imports: [
...
NgxLowerCaseDirectiveModule,
...
],
...
```
3.Add the "lowerCase" attribute to an input element or a textarea element.
```html
<input type="text" ... lowerCase>
```
4.If you want to convert the value ONLY on blur event, you should set the value of lowerCase attribute to `blur`.
```html
<textarea type="text" ... lowerCase="blur"></textarea>
```
---
Good luck.