Prefix Property

A prefix used to restrict the results returned when listing blobs or containers.

Syntax

 azureblob.getPrefix([callback])
 azureblob.setPrefix( prefix, [callback])

Default Value

""

Callback

The 'callback' parameter specifies a function which will be called when the operation completes (or an error is encountered). If the 'callback' parameter is not specified, then the method will block and will not return until the operation completes (or an error is encountered).

The callback for the getPrefix([callback]) method is defined as:

function(err, data){ }

'err' is the error that occurred. If there was no error, then 'err' is 'null'.

'data' is the value returned by the method.

The callback for the setPrefix([callback]) method is defined as:

function(err){ }

'err' is the error that occurred. If there was no error, then 'err' is 'null'.

'err' has 2 properties which hold detailed information:

err.code
err.message

Remarks

This property, if non-empty, is used to restrict the results returned by ListBlobs or ListContainers to only the items whose names begin with the given value.

Blob Namespace Traversal

By using the BlobDelimiter and Prefix properties in tandem, applications can effectively "traverse" a virtual hierarchy of blobs as if it were a filesystem. For example, assume that blobs with the following names exist within a container:

• MyCompany
• MyCompany/Department1
• MyCompany/Department2
• MyCompany/Department2/EmployeeA
• MyCompany/Department2/EmployeeB

With BlobDelimiter set to /, we can set Prefix to successively "deeper" values before calling ListBlobs for the following effect:

This property is not available at design time.

Data Type

String