The SPSiteCollection [] index operator returns a new SPSite object for each access. An SPSite instance is created even if that object was already accessed.

TypeName:	DisposeSPSiteCreatedBySPSiteCollectionIndex
CheckId:	SPC110212
Severity:	CriticalWarning
Type:	AssemblyFileReference

Resolution

The SPSiteCollection [] index operator returns a new SPSite object for each access. An SPSite instance is created even if that object was already accessed. The following code samples demonstrate improper disposal of the SPSite object. See sample (source: MSDN):

Bad Coding Practice

void SPSiteCollectionIndexerLeak()
{
  using (SPSite siteCollectionOuter = new SPSite("http://moss"))
  {
    SPWebApplication webApp = siteCollectionOuter.WebApplication;
    SPSiteCollection siteCollections = webApp.Sites;

    SPSite siteCollectionInner = siteCollections[0];
    // SPSite siteCollectionInner leak.
  } // SPSite object siteCollectionOuter.Dispose() automatically called.
}

Good Coding Practice

void SPSiteCollectionIndexerNoLeak()
{
  using (SPSite siteCollectionOuter = new SPSite("http://moss"))
  {
    SPSite siteCollectionInner = null;
    try
    {
      SPWebApplication webApp = siteCollectionOuter.WebApplication;
      SPSiteCollection siteCollections = webApp.Sites;

      siteCollectionInner = siteCollections[0];
    }
    finally
    {
      if (siteCollectionInner != null)
        siteCollectionInner.Dispose();
    }
  } // SPSite object siteCollectionOuter.Dispose() automatically called.
}

Remarks

Rule relates to SPDisposeCheckId 'SPDisposeCheckID_230'. To ignore this rule add the attribute '[SPDisposeCheckIgnore(SPDisposeCheckID.SPDisposeCheckID_230, "Caller will dispose")]' to your method.

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