图像到base64字符串

Question

我已将图像上传到名为images的文件夹中，现在我已尝试将图像转换为字符串，但它对我不起作用，这是我的代码，可以任何人重定向我正确的方向，我想将它转换为base64字符串我已经尝试了很多代码，图像现在存储在images文件夹中。

<?php
//define a maxim size for the uploaded images in Kb
define ("MAX_SIZE","1000"); 

//This function reads the extension of the file. It is used to determine if the file    is an image by checking the extension.
function getExtension($str) {
$i = strrpos($str,".");
if (!$i) { return ""; }
$l = strlen($str) - $i;
$ext = substr($str,$i+1,$l);
return $ext;
}

//This variable is used as a flag. The value is initialized with 0 (meaning no error  found)  
//and it will be changed to 1 if an errro occures.  
//If the error occures the file will not be uploaded.
$errors=0;
//checks if the form has been submitted
if(isset($_POST['Submit'])) 
{
//reads the name of the file the user submitted for uploading
$image=$_FILES['image']['name'];
//if it is not empty
if ($image) 
{
//get the original name of the file from the clients machine
$filename = stripslashes($_FILES['image']['name']);
//get the extension of the file in a lower case format
$extension = getExtension($filename);
$extension = strtolower($extension);
//if it is not a known extension, we will suppose it is an error and will not  upload the file,  
//otherwise we will do more tests
if (($extension != "jpg") && ($extension != "jpeg") && ($extension != "png") &&  ($extension != "gif")) 
{
 //print error message
 echo '<h1>Unknown extension!</h1>';
 $errors=1;
 }
 else
 {
 //get the size of the image in bytes
 //$_FILES['image']['tmp_name'] is the temporary filename of the file
 //in which the uploaded file was stored on the server
 $size=filesize($_FILES['image']['tmp_name']);

 //compare the size with the maxim size we defined and print error if bigger
 if ($size > MAX_SIZE*1024)
 {
 echo '<h1>You have exceeded the size limit!</h1>';
 $errors=1;
 }

//we will give an unique name, for example the time in unix time format
$image_name=time().'.'.$extension;
//the new name will be containing the full path where will be stored (images folder)
$newname="images/".$image_name;
//we verify if the image has been uploaded, and print error instead
$copied = copy($_FILES['image']['tmp_name'], $newname);
if (!$copied) 
{
echo '<h1>Copy unsuccessfull!</h1>';
$errors=1;
}}}}

 //If no errors registred, print the success message
 if(isset($_POST['Submit']) && !$errors) 
 {
 echo "<h1>File Uploaded Successfully! Try again!</h1>";
 function encode_img($image_name)
 {
 $fd = fopen ($image_name, 'rb');
 $size=filesize ($image_name);
 $cont = fread ($fd, $size);
 fclose ($fd);
 $encimg = base64_encode($cont);
 return $encimg;
 } 
 $image_base64=encode_img('$image_name'); 
 echo $image_base64;// to encode the image 
 }
 ?>
 <!--next comes the form, you must set the enctype to "multipart/frm-data" and use an input type "file" -->
 <form name="newad" method="post" enctype="multipart/form-data"  action="">
 <table>
 <tr><td><input type="file" name="image"></td></tr>
 <tr><td><input name="Submit" type="submit" value="Upload image"></td></tr>
 </table>   
 </form>

Answer 1

简单使用file_get_contents

$contents = file_get_contents('path to your image');
$encode   = base64_encode($contents);