Environment variables. Java_home

1. Information: (my article)

Http://www.cnblogs.com/cppskill/p/8341263.html

2.

2.1. Interface

2.2. Code

UnitFormMain;InterfaceusesWindows, Messages, sysutils, variants, Classes, Graphics, Controls, Forms, Dialogs, Stdctrls, Registry, inifiles;
    typeTfrmmain=class(tform) Btnregeditwrite:tbutton;    Memo1:tmemo;    Btnregeditread:tbutton;    Edtjavahome:tedit; procedureBtnregeditwriteclick (Sender:tobject); procedureformcreate (Sender:tobject); procedureBtnregeditreadclick (Sender:tobject);  Public    functionReadString (_dwrootkey:D Word;Const_strpath, _strkey:string;var_strout:string): Integer; functionWriteString (_dwrootkey:D Word;Const_strpath, _strkey, _strvalue:string): Integer;  Public    functionReadini (): integer; End;varFrmmain:tfrmmain;Implementation{$R *.DFM}functionTfrmmain.readstring (_dwrootkey:D Word;Const_strpath, _strkey:string;var_strout:string): Integer;varReg:tregistry;beginResult:=0; REG:= Tregistry.Create; TryReg. Rootkey:= _dwrootkey;//HKEY_LOCAL_MACHINE;//' SYSTEM\CurrentControlSet\Control\Session manager\environment '    if  notReg. Openkey (_strpath, False) Then    beginResult:= -1;    Exit; End; _strout:=Reg.  ReadString (_strkey); finallyReg.    Closekey; Reg.Destroy; End;End;functionTfrmmain.writestring (_dwrootkey:dword;Const_strpath, _strkey, _strvalue:string): Integer;varReg:tregistry;beginReg:= Tregistry.Create; TryReg. Rootkey:= _dwrootkey;//HKEY_LOCAL_MACHINE;//' SYSTEM\CurrentControlSet\Control\Session manager\environment '    if  notReg. Openkey (_strpath, False) Then    beginResult:= -1;    Exit; End; Reg.  WriteString (_strkey, _strvalue); finallyReg.    Closekey; Reg.Destroy; End;End;proceduretfrmmain.formcreate (sender:tobject);beginReadini; Btnregeditreadclick (Nil);End;procedureTfrmmain.btnregeditwriteclick (sender:tobject);varstrvalue:string;beginMemo1.Lines.Add ("');//hkey_local_machine\system\controlset001\session Manager\environment\path//HKEY_CURRENT_USER \environment//HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment (official)  //strvalue: = ' C:\Program files\java\jdk1.8.0_152; AAA ';  //strvalue: = ' C:\Program files\java\jdk1.8.0_152 ';strvalue: =trim (edtjavahome.text); if(strvalue ="') Then  beginMemo1.Lines.Add ('the value of the new Java_home is empty.');  Exit; End; if 0>writestring (HKEY_LOCAL_MACHINE,'system\currentcontrolset\control\session Manager\Environment','Java_home', strvalue) Then  beginMemo1.Lines.Add ('registry write failed.');  Exit; End; MEMO1.LINES.ADD ('Registry write succeeded.');End;procedureTfrmmain.btnregeditreadclick (sender:tobject);varstrvalue:string;beginMemo1.Lines.Add ("'); if(0>ReadString (HKEY_LOCAL_MACHINE,'system\currentcontrolset\control\session Manager\Environment','Java_home', strvalue)) Then  beginMemo1.Lines.Add ('Error reading Registry');  Exit; End; MEMO1.LINES.ADD ('HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\environment\java_home'); MEMO1.LINES.ADD ('   '+strvalue);End;functionTfrmmain.readini (): integer;varIni:tinifile; strX86, strX64:string; strFileName:string;beginstrFileName:= Extractfilepath (Paramstr (0)) +'_environmentvariable.ini'; INI:= Tinifile.Create(strFileName); TrystrX86:= ini. ReadString ('Java_home','win7x86',"'); STRX64:= ini. ReadString ('Java_home','win7x64',"'); MEMO1.LINES.ADD ('Java_home (win7x86):'+strX86); MEMO1.LINES.ADD ('Java_home (win7x64):'+strX64); finallyINI.  Free; End;End;End.

2.3. ini file (_environmentvariable.ini)

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Environment variables. Java_home