PHP tutorial How to use BLOB to access picture information instance ___

PHP tutorial How to use BLOB to access picture information instance ____php

Last Update:2018-07-24 Source: Internet

Author: User

Tags php tutorial

Developer on Alibaba Coud: Build your first app with APIs, SDKs, and tutorials on the Alibaba Cloud. Read more ＞

A blob is a MySQL data type called a binary large object. As its name it is used to store a large number of string data similar to the MySQL binary and varbinary type.

MySQL BLOB classification

MySQL blob type maximum storage length (bytes)
Tinyblob (1) (2 ^ 8)
Blob ((2 ^ 16) 1)
Mediumblob ((2 ^ 24) 1)

Longblob ((2 ^ 32) 1)

In this tutorial, we learned how to insert and read a MySQL blob field using PHP .

(Ps:t good PHP Q-Buckle 峮: 276167802, Validation: CSL)

First, we need to create a MySQL table with a BLOB field.

CREATE TABLE IF not EXISTS ' output_images ' (
  ' imageID ' tinyint (3) is not NULL auto_increment,
  ' imagetype ' varchar (25 Not null DEFAULT ',
  ' imagedata ' mediumblob not NULL,
  PRIMARY KEY (' imageID ')

Inserting data

Inserts picture information into the MySQL blob field.

1, upload image files.

2, Get Image properties (image data, image types, etc.). )

3, image file insertion blob.

PHP Implementation script:

imageupload.php

<?php if (count ($_files) > 0) {if (Is_uploaded_file ($_files[' userimage '] [' tmp_name '])) {mysql_connect ("
LocalHost "," root "," "");
mysql_select_db ("Phppot_examples");
$imgData =addslashes (file_get_contents ($_files[' userimage '] [' tmp_name ']);
$imageProperties = getimagesize ($_files[' userimage '] [' tmp_name ']);
$sql = "INSERT into Output_images (imagetype, ImageData) VALUES (' {$imageProperties [' MIME ']} ', ' {$imgData} ')";
$current _id = mysql_query ($sql) or Die ("<b>Error:</b> Problem on Image insert<br/>". Mysql_error ());
if (Isset ($current _id)) {header ("Location:listImages.php");}}} ?> <HTML> <HEAD> <title>upload Image to MySQL blob</title> <link href= "Imagestyles.css" Rel= "stylesheet" type= "Text/css"/> </HEAD> <BODY> <form name= "frmimage" enctype= "multipart/" Form-data "action=" "method=" Post "class=" Frmimageupload "> <label>upload Image file:</label><br/ > <input name= "userimage" type= "file" class= "Inputfile "/> <input type=" Submit "value=" Submit "class=" btnsubmit "/> </form> </div> </body > </HTML>

The upload form after executing this script will appear as follows:

Submit the form, PHP gets the file of the content image and stores it as binary data into the MySQL BLOB column.

Show pictures

To display a BLOB image on the browser, we must:

1. Get image data and type from MySQL blob

2. Set the type to image (Image/jpg, image/gif, ...) Use the PHP header () function.

3, Output image content.

imageview.php

<?php
$conn = mysql_connect ("localhost", "root", "");
mysql_select_db ("Phppot_examples") or Die (Mysql_error ());
if (Isset ($_get[' image_id ')) {
$sql = "Select Imagetype,imagedata from Output_images WHERE imageid=". $_get[' Image_ Id '];
$result = mysql_query ("$sql") or Die ("<b>Error:</b> Problem on retrieving Image blob<br/>"
. mysql _error ());
$row = Mysql_fetch_array ($result);
Header ("Content-type:"). $row ["imagetype"]);
echo $row ["ImageData"];
}
Mysql_close ($conn);
? >

The PHP code above will display a picture of the MySQL blob stored. From the HTML image tag we can refer to this PHP file with the corresponding image_id as parameters. For example:

The complete code is as follows:

listimages.php

<?php
$conn = mysql_connect ("localhost", "root", "");
mysql_select_db ("Phppot_examples");
$sql = "Select imageID from Output_images order by imageID DESC";
$result = mysql_query ($sql);
? >
<HTML>
<HEAD>
<title>list BLOB images</title>
<link href= " Imagestyles.css "rel=" stylesheet "type=" Text/css "/>
</HEAD>
<BODY>
<?php
while ($row = Mysql_fetch_array ($result)) {
?>
<br/>
<?php
}
mysql_close ($conn);
? >
</BODY>
</HTML>

The above is this article about PHP tutorial how to use BLOB to access picture Information example, I hope this article for the vast number of PHP developers to help, thank you for reading this article.

This article is an English version of an article which is originally in the Chinese language on aliyun.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to info-contact@alibabacloud.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

Get Started for Free

Sales Support

1 on 1 presale consultation

Chat Contact Sales
After-Sales Support

24/7 Technical Support 6 Free Tickets per Quarter Faster Response

Open a Ticket
Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.

Learn More