如何在不同的富文本框中打开文件夹的内容？

Question

I'm trying to open a file dialog and open the files inside a folder into different rich text boxes? but i'm not sure what else I would need to add? could you please help out a new blood.

            if (openFileDialog1.ShowDialog() == System.Windows.Forms.DialogResult.OK)
        {
            richTextBox1.Text = File.ReadAllText(openFileDialog1.FileName);
            tabPage1.Text = openFileDialog1.SafeFileName;
        }

Answer 1

If you want to allow your user to select a folder and then open the first 5 files present in that folder each one in a different richtextbox then you don't need the OpenFileDialog , but the FolderBrowserDialog

// First prepare two list with the richtextboxes and the tabpages
List<RichTextBox> myBoxes = new List<RichTextBox>()
{ richTextBox1, richTextBox2, richTextBox3, richTextBox4, richTextBox5 };
List<TabPage> myPages = new List<TabPage>()
{ tabPage1, tabPage2, tabPage3, tabPage4, tabPage5};


// Now open the folderbrowser dialog 
// (see link above for some of its properties)
FolderBrowserDialog fbd = new FolderBrowserDialog();
if(fbd.ShowDialog() == DialogResult.OK)
{
    int i = 0;
    foreach(string file in Directory.GetFiles(fbd.SelectedPath))
    {        
        myBoxes[i].Text = File.ReadAllText(file);
        myPages[i].Text = Path.GetFileName(file);
        i++;

        // Added a warning if the folder contains more than 5 files
        if(i >= 5)
        { 
           MessageBox.Show("Too many files in folder, only 5 loaded");
           break;
        }
     }
 }

Answer 2

OpenFileDialog is to open but one file by default. Try to change its MultiSelect property to true . Something like this will do:

openFileDialog1.Multiselect = true;
if (openFileDialog1.ShowDialog() == System.Windows.Forms.DialogResult.OK) {
    for (int i = 0; i < openFileDialog1.FileNames.Length; ++i) {
        RichTextBox rtb = Controls.Cast<Control>().Single(x => x.Name == "richTextBox" + (i + 1).ToString()) as RichTextBox;
        rtb.Text = File.ReadAllText(openFileDialog1.FileNames[i]);
    }
    tabPage1.Text = openFileDialog1.SafeFileName; //again, I wonder what you want to do with this. If needed be, consider to update this dynamically too
}           

Old answer:

openFileDialog1.Multiselect = true; //important: set this to true
richTextBox1.Text = ""; //and you may want to reset this every time
if (openFileDialog1.ShowDialog() == System.Windows.Forms.DialogResult.OK) {
    foreach(var filename in openFileDialog1.FileNames) //get file names here
        richTextBox1.Text += File.ReadAllText(filename); //you may want to add enter per file
    tabPage1.Text = openFileDialog1.SafeFileName; //but I wonder what you want to do with this....?
}