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Detailed explanation of php file operation functions_PHP tutorial

Jul 20, 2016 am 10:58 AM
phpunderfunctionexistrightSummarizeIsupplyoperatedocumentofDetailed explanationread

PHP provides a large number of functions for file operations. Let me summarize the PHP file functions for file reading and writing. Friends who need to know about these functions can refer to them. ​

1. Manipulate files and obtain file information

The code is as follows Copy code
 代码如下 复制代码

    //打开文件
    $file_path="text.txt";
    if($fp=fopen($file_path,"r")){
        //取出文件的信息
        $file_info=fstat($fp);
        echo "

	";
        print_r($file_info);
        echo "
";

 

        //单个的取出
        $file_size=$file_info['size'];
        //文件大小按字节来计算的
        echo "文件的大小为:".$file_size;
        echo  "
文件上次访问的时间:".date("Y-m-d H:i:s",$file_info['atime']);  //atime表示【该文件上次被访问的时间】
        echo  "
文件上次修改的时间:".date("Y-m-d H:i:s",$file_info['mtime']);  //mtime表示【该文件上次内容被修改的时间】
        echo  "
文件上次change的时间:".date("Y-m-d H:i:s",$file_info['ctime']); //ctime表示【该文件上次 文件所有者/文件组 修改的时间】

    }else{
        echo "打开文件失败";
    }
   
    //关闭文件,这个非常重要
    fclose($fp);
?>

//Open file
$file_path="text.txt";
If($fp=fopen($file_path,"r")){
//Retrieve file information
          $file_info=fstat($fp);
echo "
 代码如下 复制代码

    //第二种获取文件信息
    $file_path="text.txt";
    if(!file_exists($file_path)){
        echo "文件不存在";
        exit();
    }

    echo "
".date("Y-m-d H:i:s",fileatime($file_path));
    echo "
".date("Y-m-d H:i:s",filemtime($file_path));
    echo "
".date("Y-m-d H:i:s",filectime($file_path));

    //echo "
".filemtime($file_path);
    //echo "
".filectime($file_path);
?>

	";
    print_r($arr);
    echo "
"; // Take out individually
          $file_size=$file_info['size'];
//File size is calculated in bytes
echo "The size of the file is:".$file_size;
echo "
The time when the file was last accessed: ".date("Y-m-d H:i:s",$file_info['atime']); //atime means [the time when the file was last accessed]
echo "
The time when the file was last modified: ".date("Y-m-d H:i:s",$file_info['mtime']); //mtime represents [the time when the content of the file was last modified]
echo "
The time when the file was last changed: ".date("Y-m-d H:i:s",$file_info['ctime']); //ctime means [the time when the file was last modified by the file owner/file group] }else{
echo "Failed to open file";
}

//Close the file, this is very important
fclose($fp);
?>
2. The second way to obtain file information
The code is as follows Copy code
//The second way to obtain file information
$file_path="text.txt";
If(!file_exists($file_path)){
echo "File does not exist";
exit();
} echo "
".date("Y-m-d H:i:s",fileatime($file_path));
echo "
".date("Y-m-d H:i:s",filemtime($file_path));
echo "
".date("Y-m-d H:i:s",filectime($file_path)); //echo "
".filemtime($file_path);
//echo "
".filectime($file_path);
?>

2. Read file operation

The code is as follows Copy code
 代码如下 复制代码

    //读取文件
    $file_path="text.txt";

    if(!file_exists($file_path)){
        echo "文件不存在";
        exit();
    }
   
    //打开文件
    $fp=fopen($file_path,"a+");
    //读取文件
    $content=fread($fp,filesize($file_path));
    echo "文件内容是:
";
    //默认情况下把内容输出到网页后,不会换行显示,因为网页不识别rn
    //所有要把rn =>

   
    $content=str_replace("rn","
",$content);
    echo  $content;

    fclose($fp);
?>


 

//Read file
$file_path="text.txt";
 代码如下 复制代码


    //第二种读取文件的方式

    $file_path="text.txt";
    if(!file_exists($file_path)){
        echo "文件不存在";
        exit();
    }
    $content=file_get_contents($file_path);

    $content=str_replace("rn","
",$content);
    echo  $content;
?>


 

if(!file_exists($file_path)){
echo "File does not exist";
exit();
}

//Open file
$fp=fopen($file_path,"a+");
//Read file
$content=fread($fp,filesize($file_path));
echo "The file content is:
";
//By default, after the content is output to the web page, it will not be displayed in a new line because the web page does not recognize rn
//Everything needs to be done =>


$content=str_replace("rn","
",$content);
echo $content;

 代码如下 复制代码


    //第三种读取方法,循环读取(对付大文件)

    $file_path="text.txt";
    if(!file_exists($file_path)){
        echo "文件不存在";
        exit();
    }

    //打开文件
    $fp=fopen($file_path,"a+");
    //定义每次读取的多少字节
    $buffer=1024;
    //一边读取。一边判断是否达到文件末尾
    while(!feof($fp)){
        //按1024个字节读取数据
        $content=fread($fp,$buffer);
        echo $content;
    }

    fclose($fp);
?>


 

fclose($fp);
?>
2. The second way to read files
The code is as follows Copy code

//The second way to read files $file_path="text.txt";
If(!file_exists($file_path)){
echo "File does not exist";
exit();
}
$content=file_get_contents($file_path); $content=str_replace("rn","
",$content);
echo $content;
?>
3. The third reading method, loop reading (for large files)
The code is as follows Copy code

//The third reading method, loop reading (for large files) $file_path="text.txt";
If(!file_exists($file_path)){
echo "File does not exist";
exit();
} //Open file
$fp=fopen($file_path,"a+");
//Defines how many bytes to read each time
$buffer=1024;
//Read while reading. Determine whether the end of the file is reached
While(!feof($fp)){
//Read data in 1024 bytes
         $content=fread($fp,$buffer);
echo $content;
} fclose($fp);
?>

4、文件读取实际应用:当我们连接数据库的时候,可以把指定的数据配置到一个文件中,然后再PHP运行时,实时获取信息

 代码如下 复制代码

db.ini 文件

host=127.0.0.1
user=root
pwd=root
db=test


获取文件

 代码如下 复制代码

    $arr=parse_ini_file("db.ini");
    echo "

	";
    print_r($arr);
    echo "
";
   
    echo $arr['host'];

 

    //连接数据库
    $conn = mysql_connect($arr['host'], $arr['user'], $arr['pwd']);

    if(!$conn){
        echo "error";
    }

    echo "OK";
?>

三、写文件

 代码如下 复制代码

    //写文件
    $file_path="text.txt";
    if(!file_exists($file_path)){
        echo "文件不存在";
        exit();
    }
    //"a+" 在文件后面追加  "w+"重新写入

    $fp=fopen($file_path,"w+");
    $con="rn你好";
    for($i=0;$i     fwrite($fp,$con);}

    echo "添加成功";
    fclose($fp);

   
?>

2、第二中方式  通过file_put_contents函数

 代码如下 复制代码


    //第二种方式写文件
    $file_path="text.txt";
    $content="hello,worldrn";

    //将一个字符串写入文件  默认是【FILE_USE_INCLUDE_PATH 】"w+"重新写入
    file_put_contents($file_path,$content,FILE_APPEND);

    echo "OK";
?>


www.bkjia.comtruehttp://www.bkjia.com/PHPjc/445636.htmlTechArticle在php中提供了大量的对文件操作的函数,下面我来给大家总结php 文件函数对文件读入,写入操作,有需了解的这些函数的朋友可进入参考。...
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