php 用txt文本文件做数据库程序

define ("tblPath",".");
define ("exten",".php");
define ("fileHead","This file only for class txtTbl");
class txtTbl {
var $innerName=""; //数据库名称
var $innerCount; //数据库记录数目
var $innerFields; //数据库字段列表数组
var $inner_F_Count; //数据库字段数目
var $fullName; //完整的文件名
var $isModify = false; //当前记录是否被修改
var $fileModify = false; //数据库是否被修改
var $innerRecorders; //数据库记录数组
var $curLine; //当前记录号
var $curArray; //当前行数组
var $stringDel; //保存被删除记录
var $sprt1; //数据库记录间的分隔符
var $sprt2; //数据库字段间的分隔符
var $innerBof = true;
var $innerEof = false;

function create($tblName,$fields,$sprt1="<---txtTbl--->n",$sprt2="<---txtTbl--->"){
if (empty($tblName)){
echo "The textDateBase file name not appoint.";
return false;
}
$fullName = tblPath.$tblName.exten;
if (file_exists($fullName)){
echo "The textDateBase file is already exist.";
return false;
}
if(empty($fields)){
echo "The fields list Array is invalid.";
return false;
}
$cont = implode($sprt2,$fields);
$cont = fileHead."n".$cont;
$fp = fopen($fullName,"w");
fwrite($fp,$cont);
fclose($fp);
return true;
}

function drop($tblName,$sprt1="<---txtTbl--->n",$sprt2="<---txtTbl--->"){
if (empty($tblName)){
echo "The textDateBase file name not proveid.";
return false;
}
if (!empty($this->innerName)){
echo "Current file not closed,Please close it and try again.";
return false;
}
$fullName = tblPath.$tblName.exten;
if (!file_exists($fullName)){
echo "The textDateBase file not exist.";
return false;
}
$fp = fopen($fullName,"r");
if (!feof($fp)){
$readFromFile = fgets($fp);
}
if ($readFromFile!=fileHead."n"){
fclose($fp);
echo "not a valid textDataBase file.(the head is invalid.)"."n";
return false;
}
$readFromFile = "";
if (!feof($fp)) $readFromFile.= fgets($fp);
fclose($fp);
$readFromFile = trim($readFromFile);
if (empty($readFromFile)){
echo "not a valid textDataBase file.(can't find fields define.)";
return false;
}
$cont = fileHead."n".$readFromFile;
$fp = fopen($fullName,"w");
fwrite($fp,$cont);
fclose($fp);
return true;
}


function open($tblName,$sprt1="<---txtTbl--->n",$sprt2="<---txtTbl--->"){
if (empty($tblName)){
echo "The textDateBase file name not proveid.";
return false;
}
if (!empty($this->innerName)){
echo "Current file not closed,Please close it and try again.";
return false;
}
$this->fullName = tblPath.$tblName.exten;
if (!file_exists($this->fullName)){
echo "The textDateBase file not exist.";
return false;
}
$fp = fopen($this->fullName,"r");
if (!feof($fp)){
$readFromFile = fgets($fp);
}
if ($readFromFile!=fileHead."n"){
fclose($fp);
echo "not a valid textDataBase file.(the head is invalid.)"."n";
return false;
}
$readFromFile = "";
while (!feof($fp)) $readFromFile.= fgets($fp);
fclose($fp);
$readFromFile = trim($readFromFile);
if (empty($readFromFile)){
echo "not a valid textDataBase file.(can't find fields define.)";
return false;
}
$this->innerRecorders = explode($sprt1,$readFromFile);
$this->innerCount = count($this->innerRecorders) - 1;
$this->innerFields = explode($sprt2,$this->innerRecorders[0]);
$this->innerFieldsCount = count($this->innerFields);

$this->innerName = $tblName;
$this->sprt1 = $sprt1;
$this->sprt2 = $sprt2;

if ($this->innerCount==0){
$this->curLine = 0;
$this->innerEof = true;
}else{
$this->curLine = 1;
// if ($this->innerCount==1) $this->innerEof = true;
if (!$this->initRec()) return false;
}

return true;
}

function close(){
if (empty($this->innerName)) return true;
//save modify
$isModify= false;
if ($this->isModify){
$this->saveModify();
$isModify= true;
}
if(isset($this->stringDel)){
$isModify= true;
$delNo= explode(",",$this->stringDel);
foreach($delNo as $no){
$no= (integer) $no;
unset($this->innerRecorders[$no]);
}
}
if ($isModify||$this->fileModify){
$recorders= implode($this->sprt1,$this->innerRecorders);
$recorders= fileHead."n".$recorders;
$fp = fopen($this->fullName,"w");
fwrite($fp,$recorders);
fclose($fp);
}
$this->innerName="";
unset($this->innerRecorders);
unset($this->curArray);
}

function next(){
if ((!$this->innerEof)&&(!empty($this->innerName))){
if($this->curLine==$this->innerCount){
$this->innerEof = true;
return true;
}
$this->saveModify();
$this->curLine++;
if ($this->innerBof) $this->innerBof = false;
$this->initRec();
}
return false;
}

function prev(){
if ((!$this->innerBof)&&(!empty($this->innerName))){
$this->saveModify();
$this->curLine--;
if ($this->curLine == 1)
$this->innerBof = true;
if ($this->innerEof) $this->innerEof = false;
$this->initRec();
}
}

function first(){
if ($this->innerBof||empty($this->innerName))
return false;
$this->saveModify();
$this->curLine = 1;
$this->innerBof= true;
$this->innerEof = false;
$this->initRec();

}

function end(){
if ($this->innerEof||empty($this->innerName))
return false;
$this->saveModify();
$this->curLine = $this->innerCount;
$this->innerEof= true;
$this->innerBof = false;
$this->initRec();

}

function eof(){
if (empty($this->innerName)){
return false;
}else return $this->innerEof;
}

function bof(){
if (empty($this->innerName)){
return true;
}else return $this->innerBof;
}

function recNo(){
return $this->curLine;
}

function recCount(){
return $this->innerCount;
}

function fieldsCount(){
if (empty($this->innerName)){
return false;
}else return $this->inner_F_Count;
}

function getValue($field){
if ($this->curLine==0||empty($this->innerName)){
echo "Can't read current record,maybe not in use or no record.";
return false;
}
$field= $this->chkField($field);
if ($field==-1){
return false;
}
return $this->curArray[$field];
}

function setValue($field,$value){
if ($this->curLine==0||empty($this->innerName)){
echo "Can't read current record,maybe not in use or no record.";
return false;
}
$field= $this->chkField($field);
if ($field==-1){
return false;
}
$this->curArray[$field]= $value;
$this->modify= true;
}

function display($shownon=0,$sprt1="",$sprt2="",$sprt3="",$sprt4=""){
echo $sprt3;
foreach($this->curArray as $v){
if($shownon==1&&empty($v)) $v= "noValue";
echo $sprt1.$v.$sprt2;
}
echo $sprt4;
}

function location($field,$keyValue){
$field=$this->chkField($field);
if ($field==-1) return false;
for($i=$this->curLine;$i<=$this->innerCount;$i++){
if($this->curArray[$field]==$keyValue){
return true;
}
$this->next();
}
return false;
}

function del($recNo=-1){
if($this->curLine==0) return false;
$vartype= gettype($recNo);
if($vartype!="integer"){
echo "del error:check ur para type.";
return false;
}
if ($recNo==-1){
$recNo=$this->curLine;}
elseif ($recNo>$this->innerCount||$recNo<1){
echo "del error:out over the rang.";
return false;
}
if (!$this->chkDel($recNo)){
if(isset($this->stringDel)){
$this->stringDel.=(','.$recNo);
}else $this->stringDel = (string) $recNo;
}else return false;
}

function append($fields=""){
$this->saveModify();
for($i=1;$i<=$this->innerFieldsCount;$i++)
$newRec[] = "";
if(!empty($fields)){
foreach($fields as $k=>$v){
$k= $this->chkField($k);
if ($k==-1){
return false;
}
$newRec[$k]= $v;
}
}
$this->innerCount++;
$this->curLine = $this->innerCount;
$this->innerBof = false;
$this->innerEof = true;
unset($this->curArray);
$this->curArray = &$newRec;
$this->isModify = true;
}

//保存修改
function saveModify(){
if($this->isModify){
$this->innerRecorders[$this->curLine]= implode($this->sprt2,$this->curArray);
$this->isModify = false;
$this->fileModify= true;
}
}

//当指针发生变化时，初始化当前记录数组
function initRec(){
$this->curArray = explode($this->sprt2,$this->innerRecorders[$this->curLine]);
if (count($this->curArray)!=$this->innerFieldsCount){
echo "The Current Recorder fields count unequal to Table's.n File will close.";
$this->close();
return false;
}
return true;
}

//输出当前记录信息，设计为调试用
function ddisplay(){
if ($this->innerCount==0) return false;
foreach($this->innerFields as $v) echo $v."----";
echo "
";
foreach($this->curArray as $v) echo $v."---";
}

//检查记录是否已被删除
function chkDel($key){
if (empty($key)&&$key!=0){
echo "the key not appoint.";
return false;
}
if (!isset($this->stringDel)){
return false;
}
if (ereg("(^|,)".$key."(,|$)",$this->stringDel)){
return true;
}
return false;
}

//检查提交的字段名是否合法.
function chkField($field){
if (empty($field)&&($field!=0)){
echo "the field not appoint.";
return -1;
}
$vartype = gettype($field);
switch ($vartype) {
case "integer":
if ($field>=$this->innerFieldsCount){
echo "the field is large than fieldscount";
return -1;
}elseif($field<0){
echo "the field is less than 0";
return -1;
}
return $field;
case "string":
foreach ($this->innerFields as $k=>$v) if ($field==$v) return $k;
echo "the field name not found.";
return -1;
default:
echo "the field is invalid.";
return -1;
}
}

}