Introduction
In Adobe ColdFusion, the <cfdump> tag is a handy tool that developers often use to debug their code by displaying the contents of variables. This tag can present data in different formats, making it easier to visualize and understand complex structures like arrays, queries, and objects. One of the key attributes of the <cfdump> tag is the format attribute, which allows developers to choose between HTML and plain text output for displaying the variable data.
This tutorial demonstrates how to use the format attribute in the <cfdump> tag with a simple example involving a ColdFusion structure. The example shows how to switch between HTML and text formats for dumping variable content, which can be particularly useful in different development environments or when rendering output in specific formats for different devices.
Understanding the Structure
In the provided example, a structure called Color is created using ColdFusion's StructNew() function. This structure represents a color object with three properties: ID, Name, and Value. The ID is a numerical identifier, the Name holds a string representing the color name (in this case, "Bisque"), and the Value contains the hexadecimal code for the color.
Once the structure is created and populated with data, the <cfdump> tag is used to display its contents in two different formats: HTML and plain text. This demonstrates how the format attribute can be utilized to output the same data in two distinct ways, depending on the development or debugging needs.
Using the HTML Format
The first <cfdump> tag in the example uses the format="html" attribute to display the Color structure in an HTML-friendly format. This is the default behavior of the <cfdump> tag if no format is specified, but explicitly setting format="html" ensures the output is structured for the web. In this format, the output appears as a well-organized table, making it easy to read and navigate, especially when debugging in a browser.
HTML output is typically used in web-based applications because it leverages the browser's ability to render the data in a visually appealing and interactive format. This format is particularly useful for reviewing the structure and content of complex data types like arrays, structures, and queries.
Using the Text Format
The second <cfdump> tag in the example switches the format attribute to "text". When format="text" is used, the output is rendered in plain text, which is useful in environments where HTML is not suitable, such as log files, terminal windows, or non-visual interfaces. The plain text format strips away the HTML tags and styles, showing only the raw data, which can be beneficial for quick and simple debugging without the need for a browser.
Text output is often preferable when developers need to review the raw content of a variable without any visual aids, or when the output needs to be processed further by text-based tools or scripts.
Conclusion
This tutorial demonstrated the use of the format attribute in the ColdFusion <cfdump> tag, illustrating how you can control the way data is displayed—either in HTML or plain text format. The ability to switch between these formats adds flexibility to the debugging process, allowing developers to choose the most appropriate format based on their current environment or requirements.
Whether you're working in a browser or a text-based environment, the <cfdump> tag provides a powerful and simple way to inspect ColdFusion variables and structures. Understanding how to use the format attribute effectively can make your debugging process smoother and more adaptable to various scenarios.
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>cfdump tag: how to use format (html, text) attribute in cfdump in coldfusion</title>
</head>
<body>
<h2 style="color:DodgerBlue; font-style:italic">cfdump tag example: how to use format (html, text) attribute</h2>
<hr width="600" align="left" color="CadetBlue" />
<br />
<cfset Color=StructNew()>
<cfset Color.ID=1>
<cfset Color.Name="Bisque">
<cfset Color.Value="##FFE4C4">
<cfdump var="#Color#" label="Color [Format html]" format="html">
<br /><br />
<cfdump var="#Color#" label="Color [format text]" format="text">
</body>
</html>
