?
Solved

Cannot change ReadOnly property for the expression column

Posted on 2009-07-02
3
Medium Priority
?
2,351 Views
Last Modified: 2012-06-21
I have a data table which I add a boolean column to.  When I later in the code try to change a value, I get an error that the column is read only.  


dt.Columns.Add("Flag", GetType(Boolean), "False")
.
.
.
Later, in my code
dt.Rows(z)("Flag") = True  '  ==>  Errors - 'Flag' is read only

So, I tried to add ReadOnly = False in my column add code, but I get Cannot change ReadOnly property for the expression column error:

dt.Columns.Add("Flag", GetType(Boolean), "False").ReadOnly = False

0
Comment
Question by:robjay
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
3 Comments
 
LVL 3

Accepted Solution

by:
jbeasle3 earned 2000 total points
ID: 24768794
Try doing this:  it seems to work where entering the expression in the add function doesn't

dc = New DataColumn("Flag", GetType(Boolean))
dc.DefaultValue = False
dt.Columns.Add(dc)
.
.
dt.Rows(0)("Flag") = True
0
 
LVL 41

Expert Comment

by:guru_sami
ID: 24768881
Add datacolum like this:
DataColumn dtc = new DataColumn();
            dtc.ColumnName = "Flag";
            dtc.DataType = System.Type.GetType("System.Boolean");
            dtc.ReadOnly = false;
            dt.Columns.Add(dtc);
0
 

Author Closing Comment

by:robjay
ID: 31599404
Just had to also add
Dim dc as New Data.DataColumn
0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Lots of people ask this question on how to extend the “MembershipProvider” to make use of custom authentication like using existing database or make use of some other way of authentication. Many blogs show you how to extend the membership provider c…
IntroductionWhile developing web applications, a single page might contain many regions and each region might contain many number of controls with the capability to perform  postback. Many times you might need to perform some action on an ASP.NET po…
Michael from AdRem Software outlines event notifications and Automatic Corrective Actions in network monitoring. Automatic Corrective Actions are scripts, which can automatically run upon discovery of a certain undesirable condition in your network.…
In this video, Percona Solutions Engineer Barrett Chambers discusses some of the basic syntax differences between MySQL and MongoDB. To learn more check out our webinar on MongoDB administration for MySQL DBA: https://www.percona.com/resources/we…
Suggested Courses
Course of the Month15 days, 17 hours left to enroll

743 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question