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Combining php and html to implement code for uploading image files to the server

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Aug 09, 2018 am 09:54 AM

The content of this article is about the code that combines php and html to upload image files to the server. It has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.

一.html code

<body>
<form action="" method="post" enctype="multipart/form-data" name="upload_form">
 <label>选择图片文件</label>
 <input name="imgfile" type="file" accept="image/gif, image/jpeg"/>
  <input name="upload" type="submit" value="上传" />
</form>
</body>

二.php code

if (isset($_FILES[&#39;imgfile&#39;]) 
&& is_uploaded_file($_FILES[&#39;imgfile&#39;][&#39;tmp_name&#39;]))
{
 $imgFile = $_FILES[&#39;imgfile&#39;];
$upErr = $imgFile[&#39;error&#39;];
if ($upErr == 0)
{
$imgType = $imgFile[&#39;type&#39;]; //文件类型。
/* 判断文件类型，这个例子里仅支持jpg和gif类型的图片文件。*/
if ($imgType == &#39;image/jpeg&#39;
|| $imgType == &#39;image/gif&#39;)
{
$imgFileName = $imgFile[&#39;name&#39;];
$imgSize = $imgFile[&#39;size&#39;];
$imgTmpFile = $imgFile[&#39;tmp_name&#39;];
/*
 将文件从临时文件夹移到上传文件夹中。
注意：upfile这个文件夹必须先创建好，不然会报错。
*/
move_uploaded_file($imgTmpFile, &#39;upfile/&#39;.$imgFileName);
/*显示上传后的文件的信息。*/
$strPrompt = sprintf("文件%s上传成功<br>"
. "文件大小: %s字节<br>"
. "<img  src=&#39;upfile/%s&#39; alt="Combining php and html to implement code for uploading image files to the server" >"
, $imgFileName, $imgSize, $imgFileName
);
echo $strPrompt;
}
else
{
echo "请选择jpg或gif文件，不支持其它类型的文件。";
}
}
else
{
echo "文件上传失败。<br>";
switch ($upErr)
{
case 1:
 echo "超过了php.ini中设置的上传文件大小。";
break;
case 2:
 echo "超过了MAX_FILE_SIZE选项指定的文件大小。";
break;
case 3:
 echo "文件只有部分被上传。";
break;
case 4:
 echo "文件未被上传。";
break;
case 5:
 echo "上传文件大小为0";
break;
}
}
}
else
{
}

三.php code analysis:

$_FILES is an array variable used to save uploaded file information.

$_FILES['imgfile'] indicates the information of the file uploaded after the control with the file domain name 'imgfile' is submitted to the server.

An uploaded file has the following attribute information:

'name': The name of the uploaded file on the client.

'type': The MIME type of the file, such as "image/jpeg".

'size': The size of the uploaded file, in bytes.

'tmp_name': When uploading, the uploaded file will be saved in a temporary folder on the server side. You can get the temporary file name through this attribute.

'error': Error code during file upload. If the upload is successful, this value is 0. The meanings of other values are as follows:

1: Exceeds the upload file size set in php.ini.

2: The file size specified by the MAX_FILE_SIZE option is exceeded.

3: Only part of the file was uploaded.

4: The file was not uploaded.

5: The uploaded file size is 0.

The code first determines whether the $_FILES['imgfile'] variable exists. If it exists, and the file pointed to by the $_FILES['imgfile']['tmp_name'] variable is uploaded , determine the error attribute. If the attribute is 0, move the uploaded image from the temporary folder to the upfile folder, display the uploaded file information, and display the uploaded image.

If the error value is not 0, it means the upload failed and the failure message is displayed.

4. Complete code





上传图片文件

"
. "文件大小: %s字节
"
. ""
, $imgFileName, $imgSize, $imgFileName
);
echo $strPrompt;
}
else
{
echo "请选择jpg或gif文件，不支持其它类型的文件。";
}
}
else
{
echo "文件上传失败。
";
switch ($upErr)
{
case 1:
 echo "超过了php.ini中设置的上传文件大小。";
break;
case 2:
 echo "超过了MAX_FILE_SIZE选项指定的文件大小。";
break;
case 3:
 echo "文件只有部分被上传。";
break;
case 4:
 echo "文件未被上传。";
break;
case 5:
 echo "上传文件大小为0";
break;
}
}
}
else
{
/*显示表单。*/
?>
<body>
<form action="" method="post" enctype="multipart/form-data" name="upload_form">
 <label>选择图片文件</label>
 <input name="imgfile" type="file" accept="image/gif, image/jpeg"/>
  <input name="upload" type="submit" value="上传" />
</form>
</body>

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