java设置环境变量小工具

unit MainUnit;interfaceuses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, Registry;type
TfrmMain = class(TForm)
btn1: TButton;
edt1: TEdit;
lbl1: TLabel;
procedure btn1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;var
frmMain: TfrmMain; function ExpandEnvironment(const strValue: string): string;
function SetGlobalEnvironment(const envName, envValue: string; const isUser: Boolean = True): Boolean;implementation{$R *.dfm}procedure TfrmMain.btn1Click(Sender: TObject);
var
path:string;
begin
SetGlobalEnvironment('JAVA_HOME',edt1.Text);
SetGlobalEnvironment('CLASSPATH','.;%JAVA_HOME%/jre/lib/rt.jar;%JAVA_HOME%/lib/tools.jar;%JAVA_HOME%/lib;');
path := ExpandEnvironment('%PATH%');
path := path + ';%JAVA_HOME%/bin';
SetGlobalEnvironment('PATH',path);
end;/// <summary>
/// 设置系统级环境变量参数函数
/// </summary>
/// <param name="envName">环境变量名</param>
/// <param name="envValue">环境变量值</param>
/// <param name="isUser">为true表示只更新当前操作员的环境变量</param>
/// <returns></returns>
function SetGlobalEnvironment(const envName, envValue: string; const isUser: Boolean = True): Boolean;
resourcestring
REG_MLOCATION ='System/CurrentControlSet/Control/Session Manager/Environment'; // 环境变量存储在注册表中的位置
REG_ULOCATION = 'Environment';
begin
with TRegistry.Create do
try
if isUser then // 设置当前用户的环境变量
Result := OpenKey(REG_ULOCATION, True)
else // 设置系统环境变量,对所有用户有效
begin
RootKey := HKEY_LOCAL_MACHINE;
Result := OpenKey(REG_MLOCATION, True);
end; if Result then
begin
WriteString(envName, envValue); // 设置注册表中环境变量的值 SetEnvironmentVariable(PChar(envName), PChar(envValue)); // 更新当前进程的环境变量值 SendMessage(HWND_BROADCAST, WM_SETTINGCHANGE, , Integer(PChar('Environment')));
// 发送消息通知所有上层的窗口,环境参数发生变化
end;
finally
Free;
end;
end;/// <summary>
/// 获取环境变量
/// </summary>
/// <param name="strValue">环境变量名</param>
/// <returns>环境变量值</returns>
function ExpandEnvironment(const strValue: string): string;
var
chrResult: array[..] of Char;
wrdReturn: DWORD;
begin
wrdReturn := ExpandEnvironmentStrings(PChar(strValue), chrResult, );
if wrdReturn = then
Result := strValue
else
begin
Result := Trim(chrResult);
end;
end;end.