我正在尝试使用 azures blob 存储实现以下目标。
- 将文件上传到 Azure Blob 存储。
- 然后发送包含文件的 base64 字符串的 http 响应。
奇怪的是,我只能让一个工作,因为它会导致另一个停止工作,具体取决于我的代码顺序。
HttpPostedFile image = Request.Files["froalaImage"];
if (image != null)
{
string fileName = RandomString() + System.IO.Path.GetExtension(image.FileName);
string companyID = Request.Form["companyID"].ToLower();
// Retrieve storage account from connection string.
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(
CloudConfigurationManager.GetSetting("StorageConnectionString"));
// Create the blob client.
CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
// Retrieve reference to a previously created container.
CloudBlobContainer container = blobClient.GetContainerReference(companyID);
// Create the container if it doesn't already exist.
container.CreateIfNotExists();
// Retrieve reference to a blob named "filename".
CloudBlockBlob blockBlob = container.GetBlockBlobReference(fileName);
// Create or overwrite the blob with contents from a local file.
using (image.InputStream)
{
blockBlob.UploadFromStream(image.InputStream);
byte[] fileData = null;
using (var binaryReader = new BinaryReader(image.InputStream))
{
fileData = binaryReader.ReadBytes(image.ContentLength);
}
string base64ImageRepresentation = Convert.ToBase64String(fileData);
// Clear and send the response back to the browser.
string json = "";
Hashtable resp = new Hashtable();
resp.Add("link", "data:image/" + System.IO.Path.GetExtension(image.FileName).Replace(@".", "") + ";base64," + base64ImageRepresentation);
resp.Add("imgID", "BLOB/" + fileName);
json = JsonConvert.SerializeObject(resp);
Response.Clear();
Response.ContentType = "application/json; charset=utf-8";
Response.Write(json);
Response.End();
}
}
上面的代码会将文件上传到 azure 的 blob 存储,但 base64 字符串将为空。
但是如果我将行 blockBlob.UploadFromStream(image.InputStream);
放在行 string base64ImageRepresentation = Convert.ToBase64String(fileData);
我将毫无问题地获取 base64 字符串,但是该文件未正确上传到 azure 的 blob 存储。
最佳答案
也许您需要在第一次使用后重置流位置?
image.InputStream.Seek(0, SeekOrigin.Begin);
关于c# - 将文件上传到 azure blob 存储,然后使用文件的 base64 字符串发送 http 响应不起作用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/46418526/