Save data of a two-column listbox to file and load it

I am working on a list program that contains a 2-column listbox. Both columns contain strings that I wish to save as a file. The file format doesn开发者_Go百科't really matter as long as it can be read and populate the listbox again at startup.

Any help will be extremely appreciated!

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You could populate your list box from a custom object and serialize that object to disk:

using System;
using System.IO;
using System.Xml;
using System.Xml.Serialization;
using System.Collections.Generic;
using System.Windows.Forms;


//Serialize an object to disk (properties must be public):

public string Serialize(Object Input, string OutFile)
{
    System.IO.MemoryStream memoryStream = new System.IO.MemoryStream();

    XmlSerializer XML = new XmlSerializer(Input.GetType());
    XML.Serialize(memoryStream, Input);

    memoryStream.Flush();
    memoryStream.Position = 0;

    if (!string.IsNullOrEmpty(OutFile))
    {
        using (FileStream fileStream = new FileStream(OutFile, FileMode.Create))
        {
            byte[] data = memoryStream.ToArray();
            fileStream.Write(data, 0, data.Length);
            fileStream.Close();
        }
    }

    return new System.IO.StreamReader(memoryStream).ReadToEnd();
}


//Deserialize from a serialized file:

    public object DeserializeFile(Type ObjectType, string FileName)
{
    Type type = typeof(object);

    if (ObjectType != null)
    { type = ObjectType; }

    using (FileStream fileStream = new FileStream(FileName, FileMode.Open, FileAccess.Read))
    {
        StreamReader sr = new StreamReader(fileStream);
        string XML = sr.ReadToEnd();

        XmlSerializer xmlSerializer = new System.Xml.Serialization.XmlSerializer(type);
        fileStream.Close();

        return xmlSerializer.Deserialize(new StringReader(XML));
    }
}

CustomObject co = DeserializeFile(typeof(CustomObject), fileName.xml) as CustomObject;

I use this method to save the contents of a CheckedListBoxControl to disk so users are able to define it with their own items.

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First off, the display of your data and what gui widgets you use is completely irrelevant (i.e. that you are using a "2 column listbox" doesn't matter). What is relevant (in this case of a listbox) is the collection of objects that is bound to your listbox.

The collection class is really the important element here for the purposes of loading & saving. Its contents are what you will be saving and loading from your file. The listbox that displays the data doesn't care; it simply displays the data of the collection it is bound to using whatever template you've setup.

So how do you load & save you ask? Here's a simple example that uses binary formatting. There are a gazillion other walkthrus on the Intertubes; just google "C# Serialization to file"

   public void Serialize(string filename, ObjectToSerialize objectToSerialize)
    {
       Stream stream = File.Open(filename, FileMode.Create);
       BinaryFormatter bFormatter = new BinaryFormatter();
       bFormatter.Serialize(stream, objectToSerialize);
       stream.Close();
    }

   public ObjectToSerialize DeSerialize(string filename)
    {
       ObjectToSerialize objectToSerialize;
       Stream stream = File.Open(filename, FileMode.Open);
       BinaryFormatter bFormatter = new BinaryFormatter();
       objectToSerialize = (ObjectToSerialize)bFormatter.Deserialize(stream);
       stream.Close();
       return objectToSerialize;
    }

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Look into the StreamReader and StreamWriter classes.

For saving the listbox contents:

   using (StreamWriter tWrite = new StreamWriter(@"c:\temp\test.txt"))
    {
      foreach (string tItem in listBox1.Items)
      {
        tWrite.WriteLine(tItem);
      }
    }

For reading file contents:

listBox1.Items.AddRange(File.ReadAllLines(@"c:\temp\test.txt"));