GM.deleteValue: Difference between revisions

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m (Whenver 8.1ish is released, this function is available currently in the trunk... created core structure doc... more explicit example could be modified and eventual link in with core API when released)
 
(Update for 4.0)
 
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{{underscore|title=GM_deleteValue}}
== Description ==
__NOTOC__


== Description ==
This method deletes an existing name / value pair from storage.
This [[API_reference|API]] method deletes an existing preference set by [[GM_setValue]].


[[#Examples|Examples]] | [[#See_Also|See Also]] | [[#Notes|Notes]]
See [[GM.setValue]] for details regarding the storage of these values.


== Syntax ==
== Syntax ==


'''GM_deleteValue(''' ''name'' ''')'''
{{Function|GM.deleteValue|name}}


:Value: Function
Compatibility: [[Version_history#4.0_2|Greasemonkey 4.0+]]
:Returns: undefined
:Compatibility: [[Version_history#8.1|Greasemonkey 8.1+]]


:{| cellpadding="5" style="border-style:solid; background:#FFFFE0;"
== Arguments ==
|+ Parameters
!style="background:#CC9900;"|'''Properties'''
|-
| <code><span style="background:#FFFFE0;">[[#name |name]]</span></code>
|}
:* All properties are optional except [[#name|name]].


[[#top|top]]
; <code>name</code>
=== Properties ===
: Property name to delete.  See [[GM.setValue#Arguments|GM.setValue]] for details on what names are valid.
----
==== <code>name</code> ====
:Value: String
:Usage: <code>'''name''' = "PropertyName";</code>


:* Property name to delete.
== Returns ==


[[#top|top]] | [[#Syntax|back]]''
A [[Promise]], resolved successfully with no value on success, rejected with no value on failure.


== Examples ==
== Examples ==
<code><pre>
GM_deleteValue("greasemonkey.scriptval.foo"));
</pre></code>


[[#top|top]]
Delete the stored name / value pair that has the name 'foo':
<pre class='sample'>
GM.deleteValue("foo");
</pre>
 
Example showing the use of [[GM.listValues]] to delete ''all'' stored name / value pairs:
<pre class='sample'>
let keys = await GM.listValues();
for (let key of keys) {
  GM.deleteValue(key);
}
</pre>
 
Similar example to the above, but with a filter within the loop to exclude 'a' and 'foo' and 'bar' from deletion:
<pre class='sample'>
let keysToKeep = ['a', 'foo', 'bar'];
let keys = await GM.listValues();
for (let key of keys) {
  if (!keysToKeep.includes(key)) {
    GM.deleteValue(key);
  }
}
</pre>


== See Also ==
== See Also ==
* [[GM_getValue]]
* [[GM_setValue]]
* [[GM_listValues]]
[[#top|top]]


== Notes ==
* [[GM.getValue]]
* [[GM.setValue]]
* [[GM.listValues]]


[[#top|top]]
[[Category:API_Reference|D]]
[[Category:API_Reference|D]]

Latest revision as of 14:23, 3 November 2017

Description

This method deletes an existing name / value pair from storage.

See GM.setValue for details regarding the storage of these values.

Syntax

function GM.deleteValue( name )

Compatibility: Greasemonkey 4.0+

Arguments

name
Property name to delete. See GM.setValue for details on what names are valid.

Returns

A Promise, resolved successfully with no value on success, rejected with no value on failure.

Examples

Delete the stored name / value pair that has the name 'foo':

GM.deleteValue("foo");

Example showing the use of GM.listValues to delete all stored name / value pairs:

let keys = await GM.listValues();
for (let key of keys) {
  GM.deleteValue(key);
}

Similar example to the above, but with a filter within the loop to exclude 'a' and 'foo' and 'bar' from deletion:

let keysToKeep = ['a', 'foo', 'bar'];
let keys = await GM.listValues();
for (let key of keys) {
  if (!keysToKeep.includes(key)) {
    GM.deleteValue(key);
  }
}

See Also