ListVersions Method

Lists previous versions of a file resource.

Syntax

• C++
• Objective-C
• C

ANSI (Cross Platform)
int ListVersions(const char* lpszFileId);

Unicode (Windows)
INT ListVersions(LPCWSTR lpszFileId);

- (void)listVersions:(NSString*)fileId;

#define MID_BOX_LISTVERSIONS 18

IPWORKSCLOUD_EXTERNAL int IPWORKSCLOUD_CALL IPWorksCloud_Box_Do(void *lpObj, int methid, int cparam, void *param[], int cbparam[], int64 *lpllVal);

Remarks

This method lists previous versions of the file resource specified by FileId. The current version is not included in the results.

Calling this method will fire the ResourceList event once for each file version, and will also populate the Resource* properties.

If there are still more file versions available to list when this method returns, the VersionMarker property will be populated. Continue to call this method until VersionMarker is empty to accumulate all pages of results in the Resource* properties.

Note that Box only returns certain resource details when listing file versions; this is a limitation of the Box API that cannot be changed. Specifically, the following properties are returned:

• ResourceCreatedTime
• ResourceHash
• ResourceId (populated by the class for convenience)
• ResourceModifiedBy
• ResourceModifiedTime
• ResourceName
• ResourceSize
• ResourceType (always 0 (brtFile))
• ResourceVersionId

The MaxResults configuration setting can be used to control the maximum number of results to return at once.

Note that Box only tracks file versions for paid accounts.

// ResourceList event handler.
box.OnResourceList += (s, e) => {
  Console.WriteLine(e.Name + ", Version: " + e.VersionId);
};

do {
  box.ListVersions("f:09876");

  for (int i = 0; i < box.Resources.Count; i++) {
    // Process resource versions here.
  }
} while (!string.IsNullOrEmpty(box.VersionMarker));

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)