Delphi实现在局域网内传递消息程序

　　向窗体上添加两个TLabel组件、两个TEdit组件和一个TButton组件，设计完成的主界面如图1所示。

图1 主界面
　　首先声明NetMessageBufferSend函数，该函数在netapi32.dll库中：

type

　　NET_API_STATUS = LongInt;
　function NetMessageBufferSend(servername: LPCWSTR; msgname: LPCWSTR;
　fromname: LPCWSTR; buf: Pointer;
　buflen: DWORD): NET_API_STATUS;
　stdcall;external 'netapi32.dll';

　　在程序运行过程中，单击Send按钮，就会向Computer文本框指定的计算机发送Content文本框中输入的消息，响应代码如下：

procedure TForm1.Button1Click(Sender: TObject);
　var
　　WideMsg:PWideChar;
　　DestName:PWideChar;
　begin
　　DestName:=PWideChar(WideString(Edit1.Text));
　　WideMsg:=PWideChar(WideString(Edit2.Text));
　　NetMessageBufferSend(nil,DestName,nil,WideMsg,Length(Edit2.Text)*2);
end;
　　程序代码如下：

unit Unit1;

interface

uses
　Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,Dialogs, StdCtrls;

type
　NET_API_STATUS = LongInt;
　function NetMessageBufferSend(servername: LPCWSTR; msgname: LPCWSTR;
　fromname: LPCWSTR; buf: Pointer;
　buflen: DWORD): NET_API_STATUS;
　stdcall;external 'netapi32.dll';

type
　TForm1 = class(TForm)
　Edit1: TEdit;
　Label1: TLabel;
　Label2: TLabel;
　Edit2: TEdit;
　Button1: TButton;
　procedure Button1Click(Sender: TObject);
private
　{ Private declarations }

public
{ Public declarations }
end;

var

　　Form1: TForm1;
　implementation
　{$R *.dfm}
　procedure TForm1.Button1Click(Sender: TObject);
var
　WideMsg:PWideChar;
　DestName:PWideChar;
begin
　DestName:=PWideChar(WideString(Edit1.Text));
　WideMsg:=PWideChar(WideString(Edit2.Text));
　NetMessageBufferSend(nil,DestName,nil,WideMsg,Length(Edit2.Text)*2);
end;

end.