PHP text manipulation class example code

This article mainly introduces the file operation class and file download function implemented by PHP. It analyzes PHP's functions of reading, writing, creating and downloading files in the form of examples. Friends who need it You can refer to

<?php   
class CtbClass {    

           var  $file;            
           var  $index;        

       //建立一个文件并写入输入    
           function  null_write($new)    
           {    
                       $f=fopen($this->file,"w");            
                       flock($f,LOCK_EX);    
                       fputs($f,$new);            
                       fclose($f);      
           }    
           //  添加数据记录到文件末端    
           function  add_write($new)  {              
                       $f=fopen($this->file,"a");            
                       flock($f,LOCK_EX);    
                       fputs($f,$new);              
                       fclose($f);      
           }      
           //  配合readfile()的返回一起使用,把一行数据转换为一维数组    
           function  make_array($line)  {    
                       $array  =  explode("\x0E",$line);    
                       return  $array;    
           }    

           //把为一维数组转换一行数据    
           function  join_array($line)  {    
                       $array  =  join("\x0E",$line);    
                       return  $array;    
           }    
           //  返回数据文件的总行数    
           function  getlines()  {    
                       $f=file($this->file);            
                       return  count($f);            
           }    
           //  返回下一行的数据记录(备用)    
           function  next_line()  {    
                       $this->index=$this->index++;            
                       return  $this->get();            
           }    

           //  返回上一行的数据记录(备用)    
           function  prev_line()  {    
                       $this->index=$this->index--;            
                       return  $this->get();            
           }        
           //  返回当前行的数据记录数据较小    
           function  get()  {    
                       $f=fopen($this->file,"r");            
                       flock($f,LOCK_SH);    
                       for($i=0;$i<=$this->index;$i++)  {    
                                   $rec=fgets($f,1024);            
                       }    
                       $line=explode("\x0E",$rec);    
                       fclose($f);    
                       return  $line;            
           }        
           //  返回当前行的数据记录数据较大    
           function  get_big_file()  {    
                       $f=fopen($this->file,"r");            
                       flock($f,LOCK_SH);    
                       for($i=0;$i<=$this->index;$i++)  {    
                                   $rec=fgets($f,1024*5);            
                       }    
                       $line=explode("\x0E",$rec);    
                       fclose($f);    
                       return  $line;            
           }        
           //  打开数据文件---以一维数组返回文件内容    
           function  read_file()  {    
                       if  (file_exists($this->file))  {    
                                   $line  =file($this->file);    
                       }    
                       return  $line;    
           }    
           //  打开数据文件---以二维数组返回文件内容    
           function  openFile()  {    
                       if  (file_exists($this->file))  {    
                                   $f  =file($this->file);    
                                   $lines  =  array();    
                                   foreach  ($f  as  $rawline)  {    
                                               $tmpline  =  explode("\x0E",$rawline);    
                                               array_push($lines,  $tmpline);    
                                   }    
                       }    
                       return  $lines;    
           }    
           //  传入一个数组,合并成一行数据,重写整个文件    
           function  overwrite($array){    
                       $newline  =  implode("\x0E",$array);                
                       $f  =  fopen($this->file,"w");    
                       flock($f,LOCK_EX);    
                       fputs($f,$newline);    
                       fclose($f);    
           }    

           //  添加一行数据记录到文件末端    
           function  add_line($array,$check_n=1)  {        
                       $s=implode("\x0E",$array);            
                       $f=fopen($this->file,"a");            
                       flock($f,LOCK_EX);    
                       fputs($f,$s);            
                       if  ($check_n==1)  fputs($f,"\n");            
                       fclose($f);      
           }            

           //  插入一行数据记录到文件最前面    
           function  insert_line($array)  {    
                       $newfile  =  implode("\x0E",$array);    
                       $f  =  fopen($this->file,"r");    
                       flock($f,LOCK_SH);    
                       while  ($line  =  fgets($f,1024))  {    
                                   $newfile  .=  $line;    
                       }    
                       fclose($f);    
                       $f  =  fopen($this->file,"w");    
                       flock($f,LOCK_EX);    
                       fputs($f,$newfile);    
                       fclose($f);    
           }    

           //  更新所有符合条件的数据记录,适用于每行字节数据较大的情况    
           function  update($column,$query_string,$update_array)  {    
                       $update_string  =  implode("\x0E",$update_array);          
                       $newfile  =  "";                
                       $fc=file($this->file);    
                       $f=fopen($this->file,"r");    
                       flock($f,LOCK_SH);    
                       for  ($i=0;$i<count($fc);$i++)  {    
                                   $list  =  explode("\x0E",$fc[$i]);    
                                   if  ($list[$column]  !=  $query_string)  {    
                                               $newfile  =  $newfile.chop($fc[$i])."\n";    
                                   }  else  {    
                                               $newfile  =  $newfile.$update_string;    
                                   }    
                       }    
                       fclose($f);    
                       $f=fopen($this->file,"w");    
                       flock($f,LOCK_EX);    
                       fputs($f,$newfile);    
                       fclose($f);    
           }    

           //  更新所有符合条件的数据记录,适用于每行字节数据较小的情况    
           function  update2($column,$query_string,$update_array)  {    
                       $newline  =  implode("\x0E",$update_array);          
                       $newfile  =  "";    
                       $f  =  fopen($this->file,"r");    
                       flock($f,LOCK_SH);    
                       while  ($line  =  fgets($f,1024))  {    
                                   $tmpLine  =  explode("\x0E",$line);    
                                   if  ($tmpLine[$column]  ==  $query_string)  {    
                                               $newfile  .=  $newline;    
                                   }  else  {    
                                               $newfile  .=  $line;    
                                   }    
                       }    
                       fclose($f);    
                       $f  =  fopen($this->file,"w");    
                       flock($f,LOCK_EX);    
                       fputs($f,$newfile);    
                       fclose($f);    
           }    

           //  删除所有符合条件的数据记录,适用于每行字节数据较大的情况    
           function  delete($column,$query_string)  {    
                       $newfile  =  "";                
                       $fc=file($this->file);    
                       $f=fopen($this->file,"r");    
                       flock($f,LOCK_SH);    
                       for  ($i=0;$i<count($fc);$i++)  {    
                                   $list  =  explode("\x0E",$fc[$i]);    
                                   if  ($list[$column]  !=  $query_string)  {    
                                               $newfile  =  $newfile.chop($fc[$i])."\n";    
                                   }    
                       }    
                       fclose($f);    
                       $f=fopen($this->file,"w");    
                       flock($f,LOCK_EX);    
                       fputs($f,$newfile);    
                       fclose($f);    
           }            

           //  删除所有符合条件的数据记录,适用于每行字节数据较小的情况    
           function  delete2($column,$query_string){        
                       $newfile  =  "";    
                       $f  =  fopen($this->file,"r");    
                       flock($f,LOCK_SH);    
                       while  ($line  =  fgets($f,1024))  {    
                                   $tmpLine  =  explode("\x0E",$line);    
                                   if  ($tmpLine[$column]  !=  $query_string)  {    
                                               $newfile  .=  $line;    
                                   }    
                       }    
                       fclose($f);    
                       $f  =  fopen($this->file,"w");    
                       flock($f,LOCK_EX);    
                       fputs($f,$newfile);    
                       fclose($f);    
           }    

       //取得一个文件里某个字段的最大值    
           function  get_max_value($column)  {    
                       $tlines  =  file($this->file);    
                       for  ($i=0;$i<=count($tlines);$i++)  {    
                                   $line=explode("\x0E",$tlines[$i]);    
                                   $get_value[]=$line[$column];    
                       }    
               $get_max_value  =  max($get_value);    
                       return  $get_max_value;    
           }    

    
           //  根据数据文件的某个字段是否包含$query_string进行查询,以二维数组返回所有符合条件的数据    
           function  select($column,  $query_string)  {    
                       $tline  =  $this->openfile();    
                       $lines  =  array();    
                       foreach  ($tline  as  $line)  {    
                                   if  ($line[$column]  ==  $query_string)  {    
                                               array_push($lines,  $line);    
                                   }    
                       }    

                       return  $lines;    
           }    

           //  功能与function  select()一样,速度可能略有提升    
           function  select2($column,  $query_string)  {    
                       if  (file_exists($this->file))  {    
                                   $tline  =  $this->read_file();    
                                   foreach  ($tline  as  $tmpLine)  {    
                                               $line  =  $this->make_array($tmpLine);    
                                               if  ($line[$column]  ==  $query_string)  {    
                                                           $lines[]=$tmpLine;    
                                               }    
                                   }    
                       }    

                       return  $lines;    
           }    

           //  根据数据文件的某个字段是否包含$query_string进行查询,以一维数组返回第一个符合条件的数据    
           function  select_line($column,  $query_string)  {    
                       $tline  =  $this->read_file();    
                       foreach  ($tline  as  $tmpLine)  {    
                                   $line  =  $this->make_array($tmpLine);    
                                   if  ($line[$column]  ==  $query_string)  {    
                                       return  $line;    
                                               break;    
                                   }    
                       }    
           }    
           //  select  next/prev  line(next_prev  ==>  1/next,  2/prev)  by  cx    
           function  select_next_prev_line($column,  $query_string,  $next_prev)  {    
                       $tline  =  $this->read_file();    
                       $line_key_end  =  count($tline)  -  1;    
                       $line_key  =  -1;    
                       foreach  ($tline  as  $tmpLine)  {    
                                   $line_key++;    
                                   $line  =  $this->make_array($tmpLine);    
                                   if  ($next_prev  ==  1)  {    //  next?    
                                               if  ($line[$column]  ==  $query_string)  {    
                                                           if  ($line_key  ==  0)  {    
                                                                       return  0;    
                                                           }  else  {    
                                                                       $line_key_up  =  $line_key  -  1;    
                                                                       return  $up_line;    
                                                           }    
                                               }  else  {    
                                                           $up_line  =  $line;    
                                               }    
                                   }  elseif  ($next_prev  ==  2)  {    //  prev?    
                                               if  ($line[$column]  ==  $query_string)  {    
                                                           if  ($line_key  ==  $line_key_end)  {    
                                                                       return  0;    
                                                           }  else  {    
                                                                       $line_key_down  =  $line_key  +  1;    
                                                                       break;    
                                                           }    
                                               }    
                                   }  else  {    
                                               return  0;    
                                   }    
                       }    
                       $down_line  =  $this->make_array($tline[$line_key_down]);    
                       return  $down_line;    
           }    

    
}   
?>

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