Question

怎样用C#获取一个文件的大小

Answer 1

 static void Main(string[] args){
 
            const string fileName = "test.txt";  // 首先在bin目录建立一个test.txt文件

            FileInfo f = new FileInfo(fileName);
            long s1 = f.Length;

            File.AppendAllText(fileName, "Hello.");

            FileInfo f2 = new FileInfo(fileName);
            long s2 = f2.Length;

            long change = (s2 - s1)*2;
            Console.WriteLine("文件大小:" + change.ToString()+"byte");
            Console.ReadKey(true);
 }

Answer 2

使用 FileInfo ，添加引用IO，
OpenFileDialog op1 = new OpenFileDialog();
if (op1.ShowDialog() == DialogResult.OK)
{
FileInfo fi = new FileInfo(op1.FileName);
this.Text = (fi.Length/1024).ToString()+"kb";
}