Providing Default Values for Text Fields in PHP

Home > PHP

Q

How To Supply Default Values for Text Fields in PHP?

✍: FYIcenter.com

A

If you want to provide a default value to a text field in your form, you need to pay attention to following notes:

The default value should be provided in the 'VALUE=default_value' attribute in the <INPUT TYPE=TEXT ...> tag.
The length of the default value should be less than the max length specified in the "MAXLENGTH=nnn" attribute. If you provide default value longer than the max length, the default value will be truncated when submitted.
You should put the default value inside double-quotes as 'VALUE="$default_value"' to protect spaces.
You must apply htmlspecialchars() translation function to the default value to protect HTML sensitive characters, like double quotes.

The PHP script below is a modified version of submit_comments.php with a default value in the "comment" field:

<?php
  $comment = 'I want to say: "It\'s a good site! :->"';
  $comment = htmlspecialchars($comment);
  print("<html><form action=processing_forms.php method=post>");
  print("<table><tr><td colspan=2>Please enter and submit your"
    ." comments about FYICenter.com:</td></tr>");
  print("<tr><td>Your Name:</td>"
    ."<td><input type=text name=name></td></tr>\n");
  print("<tr><td>Comments:</td>"
    ."<td><input type=text name=comment value=\"$comment\" size=40>"
    ."</td></tr>\n");
  print("<tr><td colspan=2><input type=submit><td></tr></table>\n");
  print("</form></html>\n");
?>

If you view this PHP page, you will a form with default value nicely displayed in the comment field. If you submit the form, you will get something like this:

Number of values: 2
  name = Alan
  comment = I want to say: \"It\'s a good site! :->\"

Notice that special characters are protected with slashes when form is submitted. See the next tip on how to remove slashes.

⇒ Removing Slashes on Submitted Input Values in PHP

⇐ Retrieving Input Values from Checkboxes in PHP

⇑ Processing Web Forms in PHP

⇑⇑ PHP Tutorials

2016-11-13, ∼2256🔥, 0💬

💬 2022-12-14 /nme: /data

Submitting Values without Using a Form in PHP
How To Submit Values without Using a Form in PHP? If you know the values you want to submit, you can code the values in a hyper link at the end of the URL. The additional values provided at the end of a URL is called query string. There are two suggestions on how to use query strings to submit value... 2016-11-08, ∼3778🔥, 0💬

Supporting Hidden Form Fields in PHP
How To Support Hidden Form Fields in PHP? Hidden fields are special fields in a form that are not shown on the Web page. But when the form is submitted, values specified in the hidden fields are also submitted to the Web server. A hidden field can be specified with the <INPUT TYPE=HIDDEN ...&... 2016-11-08, ∼3187🔥, 0💬

Generating and Processing Form with the Same Script in PHP
How To Generate and Process a Form with the Same Script in PHP? In previous exercises, a Web form is generated by one script, and processed by another script. But you could write a single script to do both. You just need to remember to: Use same script name as the form generation script in the "acti... 2016-11-08, ∼2658🔥, 0💬

Supporting Multiple Submit Buttons in PHP
How To Support Multiple Submit Buttons in PHP? Sometimes, you may need to give visitors multiple submit buttons on a single form to allow them to submit the form for different purposes. For example, when you show your customer a purchase order in a Web form, you may give your customer 3 submit butto... 2016-11-08, ∼2331🔥, 0💬

Providing Default Values for Text Fields in PHP
How To Supply Default Values for Text Fields in PHP? If you want to provide a default value to a text field in your form, you need to pay attention to following notes: The default value should be provided in the 'VALUE=default_value' attribute in the <INPUT TYPE=TEXT ...> tag. The leng... 2016-11-13, ∼2257🔥, 0💬

Input Values of SELECT Tags in PHP
What Are Input Values of SELECT Tags in PHP? SELECT tags are used in forms to provide dropdown lists. Entries in a dropdown list are defined by OPTION tags, which can provide input values in two ways: Implicit value - Provided as <OPTION>input_va lue</OPTION>,where input_... 2016-11-13, ∼2226🔥, 0💬

Specifying Input Values for Checkboxes in PHP
How To Specify Input Values for Checkboxes in PHP? Checkboxes can be used in a form for two situations: As a single switch - One <INPUT TYPE=CHECKBOX ...> tag, with no input value specified. When submitted with button pushed down, you will receive a value of "on". When submitted with b... 2016-11-13, ∼2155🔥, 0💬

Specifying Input Values for Radio Buttons in PHP
How To Specify Input Values for Radio Buttons in PHP? Radio buttons can be used in a form for two situations: As a single switch - One <INPUT TYPE=RADIO ...> tag, with no input value specified. When submitted with button pushed down, you will receive a value of "on". When submitted wit... 2016-11-13, ∼2086🔥, 0💬

Retrieving Input Values from Checkboxes in PHP
How To Retrieve Input Values for Checkboxes Properly in PHP? If multiple input values are submitted with the same field name, like the case of a group of checkboxes, you should add ([]) to the end of the field name. This tells the PHP engine that multiple values are expected for this field. The engi... 2016-11-13, ∼2034🔥, 0💬

All rights in the contents of this web site are reserved by the individual author. fyicenter.com does not guarantee the truthfulness, accuracy, or reliability of any contents.