Gets or sets the access condition on the source blob, when the request is to copy a blob. Namespace: Microsoft.WindowsAzure.StorageClient
Assembly: Microsoft.WindowsAzure.StorageClient (in Microsoft.WindowsAzure.StorageClient.dll)
Usage
| Visual Basic |
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Dim instance As BlobRequestOptions Dim value As AccessCondition value = instance.CopySourceAccessCondition instance.CopySourceAccessCondition = value |
Syntax
| Visual Basic |
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Public Property CopySourceAccessCondition As AccessCondition |
| C# |
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public AccessCondition CopySourceAccessCondition { get; set; } |
| C++ |
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public: property AccessCondition CopySourceAccessCondition { AccessCondition get (); void set (AccessCondition value); } |
| J# |
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| JScript |
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Property Value
Type: Microsoft.WindowsAzure.StorageClient.AccessConditionA structure that specifies any conditional parameters on the request.Example
The following code example checks an access condition on the source blob and copies the blob if the condition is met.
| C# | Copy Code |
|---|---|
static void CopyOnLastModifiedCondition(Uri blobEndpoint, string accountName, string accountKey)
{
//Create service client for credentialed access to the Blob service.
CloudBlobClient blobClient =
new CloudBlobClient(blobEndpoint, new StorageCredentialsAccountAndKey(accountName, accountKey));
//Get a reference to the source blob.
CloudBlob sourceBlob = blobClient.GetBlobReference("mycontainer/myblob.txt");
sourceBlob.FetchAttributes();
//Get a reference to the destination blob.
CloudBlob destBlob = blobClient.GetBlobReference("mycontainer/copy-if-modified-since.txt");
BlobRequestOptions options = new BlobRequestOptions();
DateTime dt = new DateTime(2010, 9, 1, 0, 0, 0, DateTimeKind.Utc);
//Copy the source blob to the destination blob if the source blob has been modified since 9/1/2010.
try
{
//Copy the source blob to the destination blob if the source blob has been modified since 9/1/2010.
options.CopySourceAccessCondition = AccessCondition.IfModifiedSince(dt.ToUniversalTime());
destBlob.CopyFromBlob(sourceBlob, options);
}
catch (StorageClientException e)
{
if (e.StatusCode == HttpStatusCode.PreconditionFailed)
{
Console.WriteLine("Access condition not met - blob " +
sourceBlob.Uri +
" has not been modified since " + dt.ToUniversalTime());
}
else
{
Console.WriteLine("Error code: " + e.ErrorCode);
}
}
//Get a reference to the destination blob.
destBlob = blobClient.GetBlobReference("mycontainer/copy-if-not-modified-since.txt");
try
{
//Copy source blob to destination blob if the source blob has not been modified since 9/1/2010.
options.CopySourceAccessCondition = AccessCondition.IfNotModifiedSince(dt.ToUniversalTime());
destBlob.CopyFromBlob(sourceBlob, options);
}
catch (StorageClientException e)
{
if (e.StatusCode == HttpStatusCode.PreconditionFailed)
{
Console.WriteLine("Access condition not met - ETag for blob " +
sourceBlob.Uri +
" does not match ETag for blob " + destBlob.Uri);
}
else
{
Console.WriteLine("Error code: " + e.ErrorCode);
}
}
}
| |
Remarks
This property is applicable only to a request that will copy a blob.
The default access condition for any request to copy a blob is None.
An access condition may specify a condition that must be met for the copy operation to be performed by the service. The AccessCondition structure provides methods that can be used to specify exactly one of the following access conditions:
IfMatch, which performs a copy operation only if the specified Etag value matches the blob's Etag value.
IfNoneMatch, which performs a copy operation only if the specified Etag value does not match the blob's Etag value.
IfModifiedSince, which performs a copy operation only if the resource has been modified since the specified date and time.
IfNotModifiedSince, which performs a copy operation only if the resource has not been modified since the specified date and time.