Office.CustomProperties interface
The CustomProperties object represents custom properties that are specific to a particular mail item and specific to an Outlook add-in. For example, there might be a need for an add-in to save some data that's specific to the current message that activated the add-in. If the user revisits the same message in the future and activates the add-in again, the add-in will be able to retrieve the data that had been saved as custom properties.
To learn more about CustomProperties, see Get and set add-in metadata for an Outlook add-in.
Remarks
When using custom properties in your add-in, keep in mind that:
Custom properties saved while in compose mode aren't transmitted to recipients of the mail item. When a message or appointment with custom properties is sent, its properties can be accessed from the item in the Sent Items folder. If you want to make custom data accessible to recipients, consider using InternetHeaders instead.
The maximum length of a
CustomPropertiesJSON object is 2500 characters.Outlook on Mac doesn't cache custom properties. If the user's network goes down, mail add-ins can't access their custom properties.
Minimum permission level: read item
Applicable Outlook mode: Compose or Read
Methods
| get(name) | Returns the value of the specified custom property. |
| remove(name) | Removes the specified property from the custom property collection. To make the removal of the property permanent, you must call the |
| save |
Saves custom properties to a message or appointment. You must call the It's a good practice to have your callback function check for and handle errors from |
| save |
Saves custom properties to a message or appointment. You must call the It's a good practice to have your callback function check for and handle errors from |
| set(name, value) | Sets the specified property to the specified value. The The |
Method Details
get(name)
Returns the value of the specified custom property.
get(name: string): any;Parameters
- name
-
string
The name of the custom property to be returned.
Returns
any
The value of the specified custom property.
Remarks
Minimum permission level: read item
Applicable Outlook mode: Compose or Read
Examples
// Link to full sample: https://raw.githubusercontent.com/OfficeDev/office-js-snippets/prod/samples/outlook/15-item-custom-properties/load-set-get-save.yaml
const propertyName = $("#get-property-name").val();
const propertyValue = customProps.get(propertyName);
console.log(`The value of custom property "${propertyName}" is "${propertyValue}".`);
remove(name)
Removes the specified property from the custom property collection.
To make the removal of the property permanent, you must call the saveAsync method of the CustomProperties object.
remove(name: string): void;Parameters
- name
-
string
The name of the property to be removed.
Returns
void
Remarks
Minimum permission level: read item
Applicable Outlook mode: Compose or Read
Examples
// Link to full sample: https://raw.githubusercontent.com/OfficeDev/office-js-snippets/prod/samples/outlook/15-item-custom-properties/load-set-get-save.yaml
const propertyName = $("#remove-property-name").val();
customProps.remove(propertyName);
console.log(`Custom property "${propertyName}" removed.`);
saveAsync(callback, asyncContext)
Saves custom properties to a message or appointment.
You must call the saveAsync method to persist any changes made with the set method or the remove method of the CustomProperties object. The saving action is asynchronous.
It's a good practice to have your callback function check for and handle errors from saveAsync. In particular, a read add-in can be activated while the user is in a connected state in a read form, and subsequently the user becomes disconnected. If the add-in calls saveAsync while in the disconnected state, saveAsync would return an error. Your callback function should handle this error accordingly.
saveAsync(callback: (asyncResult: Office.AsyncResult<void>) => void, asyncContext?: any): void;Parameters
- callback
-
(asyncResult: Office.AsyncResult<void>) => void
When the method completes, the function passed in the callback parameter is called with a single parameter of type Office.AsyncResult.
- asyncContext
-
any
Optional. Any state data that is passed to the callback function.
Returns
void
Remarks
Important: In Outlook on Windows, custom properties saved while in compose mode only persist after the item being composed is closed or after Office.context.mailbox.item.saveAsync is called.
Minimum permission level: read item
Applicable Outlook mode: Compose or Read
Examples
// Link to full sample: https://raw.githubusercontent.com/OfficeDev/office-js-snippets/prod/samples/outlook/15-item-custom-properties/load-set-get-save.yaml
customProps.saveAsync((result) => {
if (result.status === Office.AsyncResultStatus.Failed) {
console.error(`saveAsync failed with message ${result.error.message}`);
return;
}
console.log(`Custom properties saved with status: ${result.status}`);
});
saveAsync(asyncContext)
Saves custom properties to a message or appointment.
You must call the saveAsync method to persist any changes made with the set method or the remove method of the CustomProperties object. The saving action is asynchronous.
It's a good practice to have your callback function check for and handle errors from saveAsync. In particular, a read add-in can be activated while the user is in a connected state in a read form, and subsequently the user becomes disconnected. If the add-in calls saveAsync while in the disconnected state, saveAsync would return an error. Your callback function should handle this error accordingly.
saveAsync(asyncContext?: any): void;Parameters
- asyncContext
-
any
Optional. Any state data that is passed to the callback function.
Returns
void
Remarks
Minimum permission level: read item
Applicable Outlook mode: Compose or Read
set(name, value)
Sets the specified property to the specified value.
The set method sets the specified property to the specified value. To ensure that the set property and value persist on the mail item, you must call the saveAsync method.
The set method creates a new property if the specified property does not already exist; otherwise, the existing value is replaced with the new value. The value parameter can be of any type; however, it is always passed to the server as a string.
set(name: string, value: string): void;Parameters
- name
-
string
The name of the property to be set.
- value
-
string
The value of the property to be set.
Returns
void
Remarks
Minimum permission level: read item
Applicable Outlook mode: Compose or Read
Examples
// Link to full sample: https://raw.githubusercontent.com/OfficeDev/office-js-snippets/prod/samples/outlook/15-item-custom-properties/load-set-get-save.yaml
const propertyName = $("#set-property-name").val();
const propertyValue = $("#property-value").val();
customProps.set(propertyName, propertyValue);
console.log(`Custom property "${propertyName}" set to value "${propertyValue}".`);
Office Add-ins