Question

如何从文本文件中读取随机行并将标签中的文本更改为该随机行，然后在我编码的拖放（下方）后，标签将更改文本。语言是c＃。我是初学者，所以如果这是一个愚蠢的问题，我道歉。

private void txt_carbs_DragEnter(object sender, DragEventArgs e)
    {
        if (e.Data.GetDataPresent(DataFormats.Text))
            e.Effect = e.AllowedEffect;
        // check if the held data format is text
        // if it is text allow the effect 
        else
            e.Effect = DragDropEffects.None;
        // if it is not text do nothing
    }

    private void txt_protien_DragEnter(object sender, DragEventArgs e)
    {
        if (e.Data.GetDataPresent(DataFormats.Text))
            e.Effect = e.AllowedEffect;
        // check if the held data format is text
        // if it is text allow the effect 
        else
            e.Effect = DragDropEffects.None;
        // if it is not text do nothing
    }

    private void txt_fats_DragEnter(object sender, DragEventArgs e)
    {
        if (e.Data.GetDataPresent(DataFormats.Text))
            e.Effect = e.AllowedEffect;
            // check if the held data format is text
            // if it is text allow the effect 
        else
            e.Effect = DragDropEffects.None;
        // if it is not text do nothing
    }

    private void txt_fats_DragDrop(object sender, DragEventArgs e)
    {
        txt_fats.Text += e.Data.GetData(DataFormats.Text).ToString();
        //add the text into the text box
    }

    private void txt_protien_DragDrop(object sender, DragEventArgs e)
    {
        txt_protien.Text += e.Data.GetData(DataFormats.Text).ToString();
        //add the text into the text box
    }

    private void txt_carbs_DragDrop(object sender, DragEventArgs e)
    {
        txt_carbs.Text += e.Data.GetData(DataFormats.Text).ToString();
        //add the text into the text box
    }

    private void lbl_term_MouseDown(object sender, MouseEventArgs e)
    {
        lbl_term.DoDragDrop(lbl_term.Text, DragDropEffects.Copy);
        // get the text from the label
    }

这也是我如何改变标签文本，但这不是随机的

StreamReader score =
            new StreamReader(file_location);
        label10.Text = score.ReadLine();

Answer 1

这不是世界上最有效的实现，但如果文件不是太大，您可以执行以下操作从文件中获取随机行，如本回答here中所述：< / p>

string[] lines = File.ReadAllLines(file_location);
Random rand = new Random();
return lines[rand.Next(lines.Length)];

如何随机化标签中的文本

1 个答案: