Hi I've declare a ISerializable class and I'm able to serialize and deserialize it ONLY if I don't modify the aspx file again. If I simply re-save the aspx file (even if not modifying anything) I would get Specified cast is not valid. error during deserialization. I suspect the problem is with ClassToSerialize c=(ClassToSerialize)b.Deserialize(ms2) but I do not have the solution. From the error it looks like casting problem but how come it worked the first time? Please help! Here is the full code and the database is MSSQL. private void Button1_Click(object sender System.EventArgs e) { SerializeAndSave(); } private void Button2_Click(object sender System.EventArgs e) { RetrieveAndDeserialize(); } void Button3_Click(object sender EventArgs e) { SqlConnection connection = new SqlConnection(Server=(local); trusted_connection=true; database=myEWS); connection.Open(); string sqlselect = DELETE from EWS_LOCATION; SqlCommand command = new SqlCommand(sqlselect connection); command.ExecuteNonQuery(); connection.Close(); } public void SerializeAndSave() { try { // instantiate a MemoryStream and a new instance of our class MemoryStream ms = new MemoryStream(); ClassToSerialize c=new ClassToSerialize(); c.name = TextBox1.Text; c.age = Convert.ToInt16(TextBox2.Text); // create a new BinaryFormatter instance BinaryFormatter b=new BinaryFormatter(); // serialize the class into the MemoryStream b.Serialize(msc); ms.Seek(00); // Show the information TextBox1.Text=Ms Length: + ms.Length.ToString(); //SqlConnection connection = new SqlConnection(Server=(local);DataBase=Northwind;User Id=sa;Password=;); SqlConnection connection = new SqlConnection(Server=(local); trusted_connection=true; database=myEWS); string sqlselect = INSERT INTO EWS_LOCATION (LocationIDLocationObject) VALUES (@location_id @location_object); SqlCommand command = new SqlCommand(sqlselect connection); // (need to write something to first and lastname columns // because of constraints) SqlParameter param0 = new SqlParameter( @location_id SqlDbType.VarChar50 ); param0.Value = LOC001; command.Parameters.Add( param0 ); SqlParameter param1 = new SqlParameter( @location_object SqlDbType.Image ); param1.Value = ms.ToArray(); command.Parameters.Add( param1 ); connection.Open(); command.ExecuteNonQuery(); connection.Close(); //Clean up ms.Close(); } catch(Exception ex) { TextBox1.Text=ex.Message; } } public void RetrieveAndDeserialize() { try { MemoryStream ms2 = new MemoryStream(); SqlConnection connection = new SqlConnection(Server=(local); trusted_connection=true; database=myEWS); connection.Open(); string value = TextBox3.Text; string sqlselect = SELECT top 1 * from EWS_LOCATION where LocationID = 'LOC001'; SqlCommand command = new SqlCommand(sqlselect connection); SqlDataReader dr = command.ExecuteReader(); dr.Read(); byte[] location_object = (byte[])dr[LocationObject]; string locid = (string)dr[LocationID]; TextBox3.Text = locid; connection.Close(); ms2.Write (location_object0location_object.Length ); ms2.Seek(00); BinaryFormatter b=new BinaryFormatter(); ClassToSerialize c=(ClassToSerialize)b.Deserialize(ms2); TextBox1.Text =Deserialized Name: + c.name; TextBox2.Text =Deserialized Age: + c.age; ms2.Close(); } catch(Exception ex) { TextBox1.Text=ex.Message; } } [Serializable()] public class ClassToSerialize : ISerializable { public int age; public string name; public ClassToSerialize() { age = 0; name = null; } //Deserialization constructor. public ClassToSerialize(SerializationInfo info StreamingContext ctxt) { //Get the values from info and assign them to the appropriate properties age = (int)info.GetValue(myage typeof(int)); name = (String)info.GetValue(myname typeof(string)); } //Serialization function. public void GetObjectData(SerializationInfo info StreamingContext ctxt) { info.AddValue(myage age); info.AddValue(myname name); } } Thanks. ES

Answer

ASP.NET deserialization problem! Please HELP!

esong2

20y

1.9k

Hi, I've declare a ISerializable class and I'm able to serialize and deserialize it ONLY if I don't modify the aspx file again. If I simply re-save the aspx file (even if not modifying anything), I would get "Specified cast is not valid." error during deserialization. I suspect the problem is with "ClassToSerialize c=(ClassToSerialize)b.Deserialize(ms2)" but I do not have the solution. From the error it looks like casting problem but how come it worked the first time? Please help! Here is the full code and the database is MSSQL. <%@ Page Language="C#" EnableViewState="false" %> <%@ import Namespace="System.IO" %> <%@ import Namespace="System" %> <%@ import Namespace="System.Runtime.Serialization" %> <%@ import Namespace="System.Runtime.Serialization.Formatters.Binary" %> <%@ import Namespace="System.Data.SqlClient" %> <%@ import Namespace="System.Data" %>

Thanks. ES