使用 StreamWriter 在文件中写入 Unicode 字符串不起作用

Question

I have this code:

string s = "آ";
StreamWriter writer = new StreamWriter("a.txt", false, Encoding.UTF8);
writer.WriteLine(s);

but when I run it I can't see any "آ" in a.txt!! There isn't any string in a.txt! It is Empty! What is problem!?! Can anyone help me???

Answer 1

You never Close() the StreamWriter .

If you call writer.Close() when you finish writing, you will see the character.

But, since it implements IDisposable you should wrap the creation of the StreamWriter in a using statement:

using(StreamWriter writer = new StreamWriter("a.txt", false, Encoding.UTF8))
{
   writer.WriteLine(s);
}

This will close the stream for you.

Answer 2

By the looks of it you're not Flush() ing or Close() ing the StreamWriter before you end your application. StreamWriter uses a buffer internally which needs to be flushed before you close your application or the StreamWriter goes out of scope otherwise the data you wrote to it will not be written to disc.

You can call Close() once you're done - although instead I would suggest using a using statement instead to also assure that your StreamWriter gets properly disposed.

string s = "آ";

using (StreamWriter writer = new StreamWriter("a.txt", false, Encoding.UTF8))
{
    writer.WriteLine(s);
}

Answer 3

Try using File.WriteAllText("a.txt", s, Encoding.UTF8); .

Answer 4

Follow, complete function for export a listview to excel with correct special characteres:

private void Exportar()
    {
        Encoding encoding = Encoding.UTF8;

        saveFileDialog1.Filter = "Arquivo Excel (*.xls)|*.xls";
        saveFileDialog1.FileName = "logs";
        saveFileDialog1.Title = "Exportar para Excel";
        StringBuilder sb = new StringBuilder();
        foreach (ColumnHeader ch in lstPesquisa.Columns)
        {
            sb.Append(ch.Text + "\t");
        }
        sb.AppendLine();
        foreach (ListViewItem lvi in lstPesquisa.Items)
        {
            foreach (ListViewItem.ListViewSubItem lvs in lvi.SubItems)
            {
                if (lvs.Text.Trim() == string.Empty)
                {
                    sb.Append(" ");
                }
                else
                {
                    string ITEM = Regex.Replace(lvs.Text, @"\t|\n|\r", "");//remover novas linhas
                    sb.Append(ITEM + "\t");
                }
            }
            sb.AppendLine();
        }
        DialogResult dr = saveFileDialog1.ShowDialog();
        if (dr == DialogResult.OK)
        {
            StreamWriter sw = new StreamWriter(saveFileDialog1.FileName, false, Encoding.UTF32);
            sw.Write(sb.ToString());
            sw.Close();
        }
    }

Answer 5

If you want to read a file from somewhere that contains these Unicode characters then you do some modifications and write back to the file, the problem arises. I was stuck with the same problem. Here is the solution that worked for me

Reading data from a file that contains Unicode characters

List<string>fileData= File.ReadAllLines("URPath",Encoding.Default).ToList());
//Any modifications
File.WriteAllLines("URPath", hstFileData,Encoding.Default);

I know this is not pretty but it worked. hope this helps!

Answer 6

Few tips:

• do you see any character in the file written in place of one you expect? If not you're not flushing and closing the stream
• StreamWriter should be able to write unicode without you having to choose encoding, but you could try to use UTF32 encoding.

Check How to: Write Text to a File