Serialize Entity Framework object, save to file, read and DeSerialize
The title should make it clear what I'm trying to do - get an Entity Framework object, serialize it into a string, save the string in a file, then load the text from the file and reserialize it into an object. Hey presto!
But of course it doesn't work else I wouldn't be here. When I try to reserialise I get an "The input stream is not in a valid binary format" error so I'm obviously missing something somewhere.
This is how I serialise and save my data:
string filePath = System.Configuration.ConfigurationManager.AppSettings["CustomersLiteSavePath"];
string fileName = System.Configuration.ConfigurationManager.AppSettings["CustomersLiteFileName"];
if(File.Exists(filePath + fileName))
{
File.Delete(filePath + fileName);
}
MemoryStream memoryStream = new MemoryStream();
BinaryFormatter binaryFormatter = new BinaryFormatter();
binaryFormatter.Serialize(memoryStream, entityFrameWorkQuery.First());
string str = System.Convert.ToBase64String(memoryStream.ToArray());
StreamWriter file = new StreamWriter(filePath + fileName);
file.WriteLine(str);
file.Close();
Which gives me a big nonsensical text file, as you'd expect. I then try and rebuild my object elsewhere:
CustomerObject = File.ReadAllText(path);
MemoryStream ms = new MemoryStream();
FileStream fs = new FileStream(path, FileMode.Open);
int bytesRead;
int blockSize = 4096;
byte[] buffer = new byte[blockSize];
while (!(fs.Position == fs.Length))
{
bytesRead = fs.Read(buffer, 0, blockSize);
ms.Write(buffer, 0, bytesRead);
}
BinaryFormatter formatter = new BinaryFormatter();
ms.Position = 0;
Customer cust = (Customer)formatter.Deserialize(ms);
And then I get the binary format error.
I'm obviously being very stupid. But in what way?
Cheers, Matt
When you've saved it, you have (for reasons best known to you) applied base-64 - but you haven't applied base-64 when reading it. IMO, just drop the base-64 completely - and write directly to the FileStream . This also saves having to buffer it in memory.
For example:
if(File.Exists(path))
{
File.Delete(path);
}
using(var file = File.Create(path)) {
BinaryFormatter ser = new BinaryFormatter();
ser.Serialize(file, entityFrameWorkQuery.First());
file.Close();
}
and
using(var file = File.OpenRead(path)) {
BinaryFormatter ser = new BinaryFormatter();
Customer cust = (Customer)ser.Deserialize(file);
...
}
as a side note, you may find that DataContractSerializer makes a better serializer for EF than BinaryFormatter .
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