New page: dateTime property (#36987)

* New page: dateTime property

* New page: dateTime property

* add intro to example

* add intro to example

* remove extra character

* updates per review

---------

Co-authored-by: wbamberg <[email protected]>

Author: estelle

files/en-us/web/api/htmlmodelement/datetime/index.md

@@ -0,0 +1,69 @@
+---
+title: "HTMLModElement: dateTime property"
+short-title: dateTime
+slug: Web/API/HTMLModElement/dateTime
+page-type: web-api-instance-property
+browser-compat: api.HTMLModElement.dateTime
+---
+
+{{ APIRef("HTML DOM") }}
+
+The **`dateTime`** property of the {{domxref("HTMLModElement")}} interface is a string containing a machine-readable date with an optional time value. It reflects the [`datetime`](/en-US/docs/Web/HTML/Element/time#datetime) HTML attribute of the {{HTMLElement("del")}} and {{HTMLElement("ins")}} elements.
+
+## Value
+
+A string. For valid string formats, see the [`datetime` valid values](/en-US/docs/Web/HTML/Element/time#valid_datetime_values).
+
+## Examples
+
+Given the following HTML:
+
+```html
+<p>The paragraph <del datetime="2021-11-01">has been</del> changed</p>
+```
+
+We can get the value of the `dateTime` attribute of the `<del>` element:
+
+```js
+const deletedText = document.querySelector("del");
+console.log(deletedText.dateTime); // "2021-11-01"
+```
+
+We can also set the `dateTime` property. Here, we create an `<ins>` element, then set the `dateTime` property of the `<ins>` element to the current date in `YYYY-MM-DD` format then insert it after the deleted text:
+
+```js
+const insertedText = document.createElement("ins");
+const now = new Date();
+insertedText.dateTime = `${now.getFullYear()}-${now.getMonth() + 1}-${now.getDate()}`;
+insertedText.appendChild(document.createTextNode("was"));
+deletedText.insertAdjacentElement("afterend", insertedText);
+```
+
+If our script ran on January 9, 2025, our HTML would be as follows:
+
+```html
+<p>
+  The paragraph <del datetime="2021-11-01">has been</del
+  ><ins datetime="2025-1-9">was</ins> changed
+</p>
+```
+
+## Specifications
+
+{{Specifications}}
+
+## Browser compatibility
+
+{{Compat}}
+
+## See also
+
+- {{HTMLElement("del")}}
+- {{HTMLElement("ins")}}
+- {{domxref("HTMLModElement")}}
+- {{domxref("HTMLModElement.cite")}}
+- {{domxref("HTMLTimeElement.dateTime")}}
+- [Date strings](/en-US/docs/Web/HTML/Date_and_time_formats#date_strings)
+- [Local date and time strings](/en-US/docs/Web/HTML/Date_and_time_formats#local_date_and_time_strings)
+- {{jsxref("Date")}}
+- {{domxref("Element.insertAdjacentElement()")}}

files/en-us/web/api/htmltimeelement/datetime/index.md

@@ -9,8 +9,8 @@ browser-compat: api.HTMLTimeElement.dateTime
 {{ APIRef("HTML DOM") }}
 
 The
-**`HTMLTimeElement.dateTime`**
-property is a string that reflects the [`datetime`](/en-US/docs/Web/HTML/Element/time#datetime) HTML attribute, containing a machine-readable form of the element's date and
+**`dateTime`**
+property of the {{domxref("HTMLTimeElement")}} interface is a string that reflects the [`datetime`](/en-US/docs/Web/HTML/Element/time#datetime) HTML attribute, containing a machine-readable form of the element's date and
 time value.
 
 ## Value
@@ -36,4 +36,7 @@ t.dateTime = "6w 5h 34m 5s";
 
 ## See also
 
-- The {{domxref("HTMLTimeElement")}} interface it belongs to.
+- {{domxref("HTMLTimeElement")}}
+- {{domxref("HTMLModElement.dateTime")}}
+- [Date strings](/en-US/docs/Web/HTML/Date_and_time_formats#date_strings)
+- [Local date and time strings](/en-US/docs/Web/HTML/Date_and_time_formats#local_date_and_time_strings)