Updating data
445
Creating an action page to update data
You can create an action page to update data with either the
cfupdate
tag or
cfquery
with the
UPDATE statement.
Creating an update action page with cfupdate
The
cfupdate
tag is the easiest way to handle simple updates from a front-end form. The
cfupdate
tag has an almost identical syntax to the
cfinsert
tag.
To use the
cfupdate
tag, you must include the primary key field(s) in your form submittal. The
cfupdate
tag automatically detects the primary key field(s) in the table that you are updating and
looks for them in the submitted form fields. ColdFusion uses the primary key field(s) to select the
record to update (therefore, you cannot update the primary key value itself ). It then uses the
remaining form fields that you submit to update the corresponding fields in the record. Your form
only needs to have fields for the database fields that you want to change.
To create an update page with cfupdate:
1
Create a ColdFusion page with the following content:
<html>
<head>
<title>Update Employee</title>
</head>
<body>
<cfif not isdefined("Form.Contract")>
<cfset form.contract = "No">
<cfelse>
<cfset form.contract = "Yes">
</cfif>
First Name:
<input type="text" name="FirstName"
value="#FirstName#"><br>
Last Name:
<input type="text" name="LastName"
value="#LastName#"><br>
Department Number:
<input type="text" name="Dept_ID"
value="#Dept_ID#"><br>
Start Date:
<input type="text" name="StartDate"
value="#StartDate#"><br>
Salary:
<input type="text" name="Salary"
value="#Salary#"><br>
Populates the fields of the update form.
This example does not use ColdFusion
formatting functions. As a result, start
dates look like 1985-03-12 00:00:00
and salaries do not have dollar signs or
commas. The user can replace the
information in any field using any valid
input format for the data.
Contractor:
<cfif #Contract# IS "Yes">
<input type="checkbox" name="Contract"
checked>Yes<br>
<cfelse>
<input type="checkbox" name="Contract">
Yes <br>
</cfif>
<br>
<input type="Submit" value="Update Information">
</form>
</cfoutput>
The Contract field requires special
treatment because a check box displays
and sets its value. The
cfif
structure
puts a check mark in the check box if the
Contract field value is Yes, and leaves the
box empty otherwise.
Code
Description
Содержание ColdFusion MX
Страница 1: ...Developing ColdFusion MX Applications...
Страница 22: ...22 Contents...
Страница 38: ......
Страница 52: ...52 Chapter 2 Elements of CFML...
Страница 162: ......
Страница 218: ...218 Chapter 10 Writing and Calling User Defined Functions...
Страница 250: ...250 Chapter 11 Building and Using ColdFusion Components...
Страница 264: ...264 Chapter 12 Building Custom CFXAPI Tags...
Страница 266: ......
Страница 314: ...314 Chapter 14 Handling Errors...
Страница 344: ...344 Chapter 15 Using Persistent Data and Locking...
Страница 349: ...About user security 349...
Страница 357: ...Security scenarios 357...
Страница 370: ...370 Chapter 16 Securing Applications...
Страница 388: ...388 Chapter 17 Developing Globalized Applications...
Страница 408: ...408 Chapter 18 Debugging and Troubleshooting Applications...
Страница 410: ......
Страница 426: ...426 Chapter 19 Introduction to Databases and SQL...
Страница 476: ...476 Chapter 22 Using Query of Queries...
Страница 534: ...534 Chapter 24 Building a Search Interface...
Страница 556: ...556 Chapter 25 Using Verity Search Expressions...
Страница 558: ......
Страница 582: ...582 Chapter 26 Retrieving and Formatting Data...
Страница 668: ......
Страница 734: ...734 Chapter 32 Using Web Services...
Страница 760: ...760 Chapter 33 Integrating J2EE and Java Elements in CFML Applications...
Страница 786: ...786 Chapter 34 Integrating COM and CORBA Objects in CFML Applications...
Страница 788: ......
Страница 806: ...806 Chapter 35 Sending and Receiving E Mail...