2017年11月26日 C#流&&窗体对话框

C#流

在顶端加入using System.IO就可以使用流

StreamReder a = new StreamReder();//读取

前面什么都可以 = sr.ReadToEnd();//用法

StreamWriter a = new StreamWriter();//写入 

窗体对话框

ColorDialog //选择颜色的对话框
FloderBrowserDialog //弹出一个对话框提示用户选择文件夹
FontDialog //弹出一个对话框提示用户选择字体或者字体颜色
OpenFileDialog //弹出一个对话框提示用户打开文件夹
SeveFileDialog //弹出一个对话框提示用户选择保存文件的位置

//字体用法
DialogResult a = fontDialog1.ShowDialog();
            if (a == DialogResult.OK)
            {
                textBox1.Font = fontDialog1.Font;
                textBox1.ForeColor = fontDialog1.Color;
            }

//打开用法
openFileDialog1.Filter = "文本文件|*.txt";
            DialogResult a = openFileDialog1.ShowDialog();
            if (a == DialogResult.OK)
            {
                string b = openFileDialog1.FileName;
                StreamReader sr = new StreamReader(b, Encoding.Default);
                textBox1.Text = sr.ReadToEnd();
            }

//保存用法
    string f = "";
        private void 保存SToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (f.Length <= )
            {
                saveFileDialog1.Filter = "文本文件|*.txt";
                saveFileDialog1.FileName = "新建文本文档";
                DialogResult a = saveFileDialog1.ShowDialog();
                if (a == DialogResult.OK)
                {
                    string s = saveFileDialog1.FileName;
                    StreamWriter sr = new StreamWriter(s);
                    sr.Write(textBox1.Text);
                    sr.Flush();
                    f = s;
                }

            }
            else
            {
                StreamWriter sr = new StreamWriter(f);
                sr.Write(textBox1.Text);
                sr.Flush();
            }
        }

//另存为用法

            saveFileDialog1.Filter = "文本文件|*.txt";
            saveFileDialog1.FileName = "新建文本文档";
            DialogResult a = saveFileDialog1.ShowDialog();
            if (a == DialogResult.OK)
            {
                string s = saveFileDialog1.FileName;
                StreamWriter sr = new StreamWriter(s);
                sr.Write(textBox1.Text);
                sr.Flush();
            }