Here’s an example of how to write an HTML text input field with placeholder text using PHP that will not submit the placeholder text if the field is not edited:
<input type="text" name="my_input" placeholder="Enter your text here" value="<?php echo isset($_POST['my_input']) ? htmlspecialchars($_POST['my_input']) : ''; ?>">In this code, we’re using PHP to set the value attribute of the input field. We first check if the $_POST['my_input'] variable is set (i.e. if the form has been submitted and the input field has a value). If it is, we use the htmlspecialchars() function to sanitize the input and set it as the value of the input field. If it’s not set (i.e. the form has not been submitted), we set the value to an empty string.
The placeholder attribute sets the placeholder text that will be displayed in the input field until the user enters text.
To make sure that the placeholder text is not submitted if the field is not edited, you can add some validation code to your form processing code. For example, you can check if the $_POST['my_input'] variable is empty and display an error message if it is.