Develop dynamic websites: choose PHP, ASP or ASP.NET

This is a question that is often asked, and it can easily lead people down the wrong path of debating Linux vs. Windows. Such debates reflect how difficult it is to analyze competing web development technologies side by side, a difficulty compounded by developers' differing opinions on any comparable operating system.

So instead of continuing to participate in such debates, we might as well look at the advantages of each technology for specific web development and operating environments. Although ASP is more similar to PHP than either is to ASP.NET, we still want to discuss ASP.NET. The reason is that developers often confuse it with ASP, and with Microsoft's efforts, ASP.NET will indeed completely replace ASP in the future.

Basic theory - overview of features
PHP - Hypertext Pre-processor
PHP is an open source server-side scripting language, which is very similar to the C language in syntax. Although originally designed for use with Linux-based Apache web server systems, PHP has now been ported to any operating system and is compatible with any standard web server software. From this we can also draw the three main advantages of PHP. First of all, it is a cross-platform technology, so PHP applications can be easily ported - of course this depends on additional components that need to be integrated, such as vendor-specific databases. Such portability also brings another advantage, that is, most web hosting providers will support PHP, so it will be very convenient to change the host as needed.

Second point, since PHP has many similarities with the C programming language, PHP is very easy to use for developers who are familiar with the relevant syntax - this syntax is also used in Java, JavaScript and Perl. Third, because it is an open source product, PHP will continue to develop rapidly. More importantly, relevant vulnerability patches will be regularly implanted into the core library for free.

In addition, under some specific programming needs, PHP shows more attractiveness to developers. First of all, PHP has built-in libraries that support the direct creation and related operations of images and PDF documents. This means that when an application calls a dynamically created menu image that contains anti-aliased text, or needs to export a page in Acrobat format, PHP will be the ideal technology to solve such problems. Although these functions can theoretically be obtained through other technologies that compete with PHP, other technologies often require the installation of third-party custom components to achieve them.

Another thing that makes PHP the best choice for writing server scripts is its good performance when dealing with problems such as connecting to mySOL or Postgres databases. Although access to mySOL or Postgres databases can be achieved through ASP technology and ODBC connections, this often requires additional configuration by the system administrator. Fortunately, this limitation has been corrected in ASP.NET, and data can be provided through mySQL when it is necessary to establish a direct database connection similar to using MS SQL Server.

ASP - Active Server Pages
Microsoft introduced ASP into Windows NT Server 4 and used it as the default platform for dynamic web applications under the IIS web server. Because it uses VBScript, a fork of the Visual Basic language, ASP was immediately popular among developers who were familiar with programming in Microsoft's IDE, Visual Studio. With the continuous development of scripting languages, researchers have not introduced many features to ASP to join the ranks of technology competition. Therefore, features such as image manipulation that can be seen in PHP are not integrated into ASP. But developers can still write (or install) third-party COM objects in the form of DLL files to complete similar work. Code can be written this way to accomplish any action the server itself allows. The drawback, of course, is that this will force developers to have to interact with the desktop system in order to configure these services - a feature that is not necessary for web developers.

The advantage of ASP is that Microsoft servers are almost everywhere in enterprise environments. In addition, MS SQL Server also has a broad market and supports ASP well (not surprising). Despite the fact that ODBC is compatible with any data source, SQL Server and file DSN access can be implemented at the code level.

ASP.NET
The debate about whether to choose ASP or PHP is becoming increasingly redundant with the rise of .NET. Indeed, the years-long debate will finally come to an end with the answer to whether to choose Java or .NET technology (or both). The only connection between ASP and ASP.NET is that both use VBScript. And .NET alone, it can use VBScript and about 20 other languages.

For ASP and PHP, the reason why ASP.NET is regarded as another language is that it runs on a completely different architecture. The former is a translation script language, while .NET is a compiled framework. This means that first of all, the running speed of Web pages will be greatly improved. At the same time, the source code is more secure and robust. In addition, ASP.NET brings a new concept to Web programming - the idea of ​​"code-behind page". According to the code-behind idea, each HTML page is driven by its own compiled programmatic instructions. As a result, HTML—or the presentation layer—is largely divorced from the application's business logic. Although such separation can also be achieved through PHP and ASP, it is not a major part of its own technology like ASP.NET.

Another benefit of ASP.NET is that it fully integrates various support for XML and Web services. A very extensive security and cryptographic system library is available for .NET, which is particularly useful for financial institutions and enterprise data applications. In terms of pitfalls, even experienced developers may find that using .NET can be confusing. Regardless of the developer's familiarity with the programming language used, for Web developers, the significant increase in difficulty in programming paradigms may become a major obstacle to their integration into ASP.NET. Hosting is also an issue for ASP.NET applications. ASP.NET does not have the same broad support from hosting providers as ASP or PHP and cannot compete at the same level.

Practice - Language Comparison
Variable Declaration


In VBScript (both ASP and ASP.NET use VBScript), it is not necessary to declare variables before using them, although the technical documentation often recommends this. Using Option Explicit declarations, developers can programmatically force variable declarations. In PHP, variables can be declared, although there is no way to force developers to do this. Indeed, variables are automatically declared before use. The advantage of PHP variables is that variables can be set as references to other variables, whereas in VBScript variables can only be defined by value.

<%
&#39; VBScript Example
Option Explicit
myVar = 1
myOtherVar = myVar
myVar = 2
 
&#39; myResult will be 3
myResult = myVar + myOtherVar
%>

<?
// PHP Example
$myVar = 1;
&#39;Use the ampersand to make a reference
$myOtherVar = &$myVar;
$myVar = 2;
// $myResult will be 4
$myResult = $myVar + $myOtherVar;
?>

Variable collection
The methods of using form and query string variables in PHP and ASP are very similar. There are many ways to access a collection of form and query string variables, such as by name or as an array. In ASP.NET the situation is much different, especially with form fields. Unlike blindly looking for submitted form variables, code-behind can know every form field in the HTML page and can trigger the check of the values ​​of these form fields based on the execution of any known event. One of these events is "postback", which is fired when the form is submitted by the user. Other events can be client-side programs and can be triggered via JavaScript. In ASP.NET, there is no qualitative difference between the two.

<%
&#39; ASP Example
myFormVal = request.form("myInputField")
myQSval = request.querystring("myQSitem")
myVal = request.item("myFormOrQSitem")
%>

<?
// PHP 4.1+ Example
$myFormVal = $_POST[&#39;myInputField&#39;];
$myQSval = $_REQUEST[&#39;myQSitem&#39;];
 
// PHP 3+ Example
$myFormVal = $HTTP_POST_VARS[&#39;myInputField&#39;];
 
// If register_globals = on
$myVal = $myFormOrQSitem;
?>

<!-- ASP.NET example -->
<html>
<script language="VB" runat=server>
Sub SubmitBtn_Click(Sender As Object, E As EventArgs)
Message.Text = "Hello " & Name.Text
End Sub
</script>
<body>
<form action="action.aspx" method="post" runat="server">
Name: <asp:textbox id="Name" runat="server"/>
<asp:button text="OK" OnClick="SubmitBtn_Click"
runat="server"/>
<asp:label id="Message" runat="server"/>
</form>
</body>
</html>

String Concatenation
PHP seems to have paid enough attention to this issue, and it allows variables to be inserted into strings without having to consider the usual concatenation issues. ASP.NET makes the whole process more troublesome and requires the help of its StringBuilder class, but ASP.NET will run much faster.

<?
// PHP Example
$link = mysql_connect("host", "user", "password")or die("mysql_error());
mysql_select_db("database") or die("Could not select database");
$query = "SELECT * FROM Table";
$result = mysql_query($query) or die(mysql_error());
 
while ($line = mysql_fetch_array($result, MYSQL_ASSOC)) {
foreach ($line as $col_value) {
//do something
}
}
?>

Connecting to the database
For database connection issues, each technology has shown its own outstanding standardization. First, in each case a connection to the database is established. For PHP, the database is selected after creation (for ASP and ASP.NET this is done during the connection phase). A query is then built and passed to the database, which may or may not result in a return record.

Since ASP.NET is more object-oriented in nature and supports complex error handling, whether it is compared to PHP or ASP, ASP.NET may need to write more code to complete simple tasks. Lots of code. But in terms of advantages, ASP.NET requires much less code to complete the function of displaying data than PHP and ASP - especially if you use the built-in datagrid control to automatically create HTML output.

<%
&#39;ASP Example
Set objConn = Server.CreateObject("ADODB.Connection")
objConn.Open "Driver={SQL Server};Server=MyServerName;" & _
"Database=myDatabaseName;Uid=;Pwd="
 
const strSQL = "SELECT * FROM Table" Set objRS = Server.CreateObject("ADODB.Recordset")
objRS.OpenstrSQL, objConn
Do While Not objRS.EOF
&#39;do something
objRS.MoveNext
Loop
%>

' ASP.NET Example

<%@ Import Namespace="System.Data" %>

<%@ Import Namespace="System.Data.SqlClient" %>

<html>
<script language="VB" runat="server">
Sub Page_Load(Sender As Object, E As EventArgs)
Dim MyConn As SqlConnection = New SqlConnection("server=(local). . . ")
Dim MyComm As SqlCommand = New SqlCommand("select * from Table", MyConn)
MyConn.Open()
Dim dr As SqlDataReader = MyComm.ExecuteReader()
MyDataGrid.DataSource = dr
MyDataGrid.DataBind()
MyConn.Close()
End Sub
</script>
<body>
<ASP:DataGrid id="MyDataGrid" runat="server"
Width="600"
BackColor="#FFFFFF"
BorderColor="#000000"
ShowFooter="false"
CellPadding=2
CellSpacing="0"
Font-Name="Verdana"
Font-Size="8pt"
HeaderStyle-BackColor="#EEEEEE"
EnableViewState="false"
/>
</body>
</html>

Conclusion

The choice of ASP, PHP or ASP.NET will ultimately depend on the needs of the application, as well as the system environment in which the application is running. A developer's familiarity with similar programming languages ​​or paradigms can also be a factor in selection. Remember that there are no perfect methods and individual circumstances will dictate which technique is the best choice. For example, using ASP.NET to create a single-page form mail application for a Windows server may seem overkill, but it is an excellent environment for ASP. If a website needs to connect to the mySQL database on the Linux Apache server, then using ASP or ASP.NET will be insufficient. The process of choosing among these competing technologies is half the battle for developers if they consider the user's individual requirements in detail in advance.

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