外部方法使用C#简单例子

1、增加引用using System.Runtime.InteropServices;

2、声明和实现的连接[DllImport("kernel32", SetLastError = true)]

3、声明外部方法public static extern int GetCurrentDirectory(int a, StringBuilder b);

4、对外部方法操作 GetCurrentDirectory(300, pathstring);

 

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using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Runtime.InteropServices; //引用外部   namespace extern {      public partial class DllImportForm : Form      {          public DllImportForm()          {              InitializeComponent();          }            [DllImport( "kernel32" , SetLastError = true )] //声明和实现的连接          public static extern int GetCurrentDirectory( int a, StringBuilder b); //外部方法                   private void btnDisplay_Click(object sender, EventArgs e)          {              StringBuilder pathstring= new StringBuilder (); //返回路径              GetCurrentDirectory( 300 , pathstring);             this .listBox1.Items.Add (pathstring );            }      } }