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Commonly used php functions_PHP tutorial

Jul 20, 2016 am 11:00 AM
bfilefopenfunctionnamephpreadwhilefunctionCommonly useddocumentread

File reading function
//File reading function
function PHP_Read($file_name) {
$fd=fopen($file_name,r);
while($bufline=fgets($fd, 4096)){
$buf.=$bufline;
}
fclose($fd);
Return $buf;
}
?>

File writing function

//File writing function
function PHP_Write($file_name,$data,$method="w") {
$filenum=@fopen($file_name,$method);
flock($filenum,LOCK_EX);
$file_data=fwrite($filenum,$data);
fclose($filenum);
Return $file_data;
}
?>

Static page generation function
//Static page generation function
function phptohtm($filefrom,$fileto,$u2u=1){
if($u2u==1){
$data=PHP_Read($filefrom);
}else{
$data=$filefrom;
}
PHP_Write($fileto,$data);
Return true;
}
?>

Specify condition information quantity retrieval function

//Specify condition information quantity retrieval function
function rec_exist($table,$where){
$query="select count(*) as num from $table ".$where;
$result=mysql_query($query) or die(nerror(1));
$rowcount=mysql_fetch_array($result);
$num=$rowcount["num"];
if ($num==0){
Return false;
}
Return $num;
}
?>
Directory deletion function
//Directory deletion function
function del_DIR($directory){
$mydir=dir($directory);
while($file=$mydir->read()){
if((is_dir("$directory/$file")) AND ($file!=".") AND ($file!="..")){
del_DIR("$directory/$file");
}else{
if(($file!=".") AND ($file!="..")){
unlink("$directory/$file");
//echo "unlink $directory/$file ok
";
}
}
}
$mydir->close();
rmdir($directory);
//echo "rmdir $directory ok
";
}
?>

Directory name validity detection function

//Directory name legality detection
function isen($str){
$ret="";
for($i=0;$i $p=ord(substr($str,$i,1));
if(($p57 & $p90 & $p122){
nerror("Does not meet the specification!");
}
$ret.=chr($p);
}
Return $ret;
}
?>
Pagination function

//Paging function
function splitlist($HALT,$LRLIST,$ECHOCNT,$paper,$table,$where,$page_id,$userid){
global $splitstr,$sumcnt;
if($paper=="" || $sumcnt==""){
$query = "select count(*) as num from $table $where";
$result = mysql_query($query);
$row = mysql_fetch_array($result);
$sumcnt=$row["num"];
if($sumcnt==0){
nerror("There is no choice to publish news in this version!");
}
$paper=1;
}
$sumpaper=($sumcnt-$sumcnt%$ECHOCNT)/$ECHOCNT;
if(($sumcnt%$ECHOCNT)!=0) $sumpaper+=1;
if($sumpaper==1 && $HALT==0) return($where);
$enwhere=base64_encode(base64_encode($where));
if(($LRLIST*2+1) if(($paper-$LRLIST) $tract=1;
$sub=$LRLIST*2+1;
}else if(($paper+$LRLIST) >= $sumpaper){
$tract=$sumpaper-($LRLIST*2);
$sub=$sumpaper;
}else{
$tract=$paper-$LRLIST;
$sub=$paper+$LRLIST;
}
}else{
$tract=1;
$sub=$sumpaper;
}
$uppaper=$paper-1;
$downpaper=$paper+1;
$startcnt=($paper-1)*$ECHOCNT;
$where.=" limit ${ startcnt },${ ECHOCNT }";
if($tract > 1) { $splitstr="【 else $splitstr="【 for($i=$tract;$i if ($i!=$paper) $splitstr.="".$i." ";
else $splitstr.="".$i." ";
}
if ($sub!=$sumpaper) $splitstr.=">> 】";
else $splitstr.=">> 】";
return($where);
}
?>

Instructions for using paging functions


/*
#### Retrieve paging function ####
Int $HALT - Whether (1/0) displays the page number bar when the search results are only divided into 1 page
Int $LRLIST - (The page number bar displays the page number-1)/2
Int $ECHOCNT - The number of records displayed on each page during retrieval
Int $paper - number of pages, prefetch: $paper=$HTTP_GET_VARS[paper];
Varchar $table - data table name, pre-attached value: $table="db.table";
Varchar $where - search conditions, pre-attached value: $where="where field='value'";

Varchar $enwhere - Encode the original $where twice with base64_encode() and submit it in the form of GET
Varchar $splitstr - page number bar output string, execute the function at the corresponding position echo $splitstr;

Variables need to be obtained before function call -
$paper=$HTTP_GET_VARS[paper];
$sumcnt=$HTTP_GET_VARS[sumcnt];
$enwhere=$HTTP_GET_VARS[enwhere];

Return (Varchar $where) - Search conditions for search statements after paging
Note: This function needs to call the error handling function nerror($error);
*/
?>



Image file upload function

//Image file upload function
function upload_img($UploadFile,$UploadFile_name,$UploadFile_size,$UploadPath,$max_size=64){

//$TimeLimit=60; //Set the timeout limit time. The default time is 30 seconds. When set to 0, there is no time limit
//set_time_limit($TimeLimit);
if(($UploadFile!= "none" )&&($UploadFile != "" )){
$FileName=$UploadPath.$UploadFile_name;
if($UploadFile_size $FileSize="(string)$UploadFile_size" . "Bytes";
}elseif($UploadFile_size $FileSize=number_format((double)($UploadFile_size / 1024), 1) . " KB";
}else{
nerror("File exceeds limit size!");
}
//{
//$FileSize="number_format((double)($UploadFile_size" / (1024 * 1024)), 1) . " MB";
// }
if(!file_exists($FileName)){
if(copy($UploadFile,$FileName)){
Return "$UploadFile_name ($FileSize)";
}else{
nerror("File $UploadFile_name upload failed!");
}
unlink($UploadFile);
}else{
nerror("The file $UploadFile_name already exists!");
}
//set_time_limit(30); //Restore the default timeout setting
}
}
?>


www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/445528.htmlTechArticleFile reading function //File reading function function PHP_Read($file_name) { $fd=fopen( $file_name,r); while($bufline=fgets($fd, 4096)){ $buf.=$bufline; } fclose($fd); return $buf; } ? Text...
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