Datagridviewcomboboxcell unable to find display member

Question

1.00/5 (1 vote)

See more:

I am trying to display data in

DataGridViewComboBoxCell

but it is saying that it was unable to find field

Quote:
Field called Contacts does not exist
at System.Windows.Forms.DataGridViewComboxBoxCell.InitializeDisplayMemberPropertyDescriptor

I am combining 2 field when using select query and given name as "Contact" and
fetching data from "Contacts" table

What I have tried:

C#

string Query = "SELECT  RTRIM(dbo.ClientName(FirstName,MiddleName,LastName)) +','+ EmailAddress as Contact FROM  Contacts WHERE  CompanyID=" + ((System.Windows.Forms.DataGridViewComboBoxCell)grvJobList.Rows[grvJobList.CurrentRow.Index].Cells["Client#"]).Value.ToString() + " And (IsDelete Is null Or IsDelete = 0 )";

DataGridViewComboBoxCell ContactCmb = new DataGridViewComboBoxCell();

using (EFDbContext db = new EFDbContext())
{
	var GetData = db.Database.SqlQuery<string>(Query);
	ContactCmb.DataSource = GetData.ToList();
}

ContactCmb.ValueMember  = "Contact";
ContactCmb.DisplayMember = "Contact";
ContactCmb.DisplayStyle = DataGridViewComboBoxDisplayStyle.ComboBox;
grvJobList.Rows[e.RowIndex].Cells[e.ColumnIndex] = ContactCmb;

"Contacts" table stucture

SQL

CREATE TABLE [dbo].[Contacts](
    [ContactsID] [int] IDENTITY(1,1) NOT NULL,
    [CompanyID] [int] NULL,
    [FirstName] [nvarchar](50) NULL,
    [MiddleName] [nvarchar](30) NULL,
    [LastName] [nvarchar](50) NULL,
    [ContactTitle] [nvarchar](50) NULL,
    [MobilePhone] [nvarchar](30) NULL,
    [EmailAddress] [nvarchar](50) NULL,
    [Notes] [nvarchar](max) NULL,
    [SpecialRiggerNUM] [nvarchar](50) NULL,
    [MasterRiggerNUM] [nvarchar](max) NULL,
    [SpecialSignNUM] [nvarchar](50) NULL,
    [MasterSignNUM] [nvarchar](max) NULL,
    [Prefix] [nvarchar](20) NULL,
    [Suffix] [nvarchar](20) NULL,
    [Address] [nvarchar](255) NULL,
    [City] [nvarchar](50) NULL,
    [State] [nvarchar](30) NULL,
    [PostalCode] [nvarchar](20) NULL,
    [Country] [nvarchar](30) NULL,
    [HomePhone] [nvarchar](30) NULL,
    [WorkPhone] [nvarchar](30) NULL,
    [FaxNumber] [nvarchar](20) NULL,
    [AlternativePhone] [nvarchar](30) NULL,
    [FieldPhone] [nvarchar](30) NULL,
    [Pager] [nvarchar](20) NULL,
    [Accounting] [bit] NULL,
    [IsChange] [bit] NULL,
    [IsNewRecord] [bit] NULL,
    [IsDelete] [bit] NULL,
    [ChangeDate] [datetime] NULL,
    CONSTRAINT [PK_Contacts] PRIMARY KEY CLUSTERED
    (
        [ContactsID] ASC
    )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]

Posted 1-Sep-21 3:08am

Devendra Sarang

Updated 1-Sep-21 23:34pm

Richard Deeming

v5

Add a Solution

Comments

Richard Deeming 1-Sep-21 11:20am

Your code is vulnerable to SQL Injection[^]. NEVER use string concatenation to build a SQL query. ALWAYS use a parameterized query.

Everything you wanted to know about SQL injection (but were afraid to ask) | Troy Hunt[^]
How can I explain SQL injection without technical jargon? | Information Security Stack Exchange[^]
Query Parameterization Cheat Sheet | OWASP[^]

Devendra Sarang 1-Sep-21 23:53pm

Right now main issue is not sql injection.

Main issue is that "DataGridViewComboBoxCell" display member is saying "Contact"
filed is not found.

I will improve query once this issue solve.

Richard Deeming 2-Sep-21 3:43am

Don't say we didn't warn you when your database is stolen or modified, and you're facing multi-million dollar fines for not securing your data properly. 🤦‍♂️

Devendra Sarang 2-Sep-21 4:43am

Bro sorry to say but please reply regarding my current issue.

I am not right now interested in sql injection

If you have solution to my current problem then help me

I am not ignoring your valuable reply. I am just try to focus on "DataGridViewComboBoxCell" issue. Once it was solved, then will start working on your suggestion too

Richard Deeming 2-Sep-21 4:52am

Since you haven't provided the structure of your database, nor the complete details of the exception, nobody can tell you what the problem is.

All we can tell you is that your code has a critical security vulnerability which is so easy to exploit that a 3 year old child can do it[^].

But if you're not interested in having dangerous mistakes in your code pointed out, then you've still got a lot of learning to do.

Devendra Sarang 2-Sep-21 5:03am

leave it. i will take help from some other webiste

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Richard Deeming · Answer 1 · 2021-09-01T23:03:00

Depending on the precise error message, either the Contacts table doesn't contain one or more of the referenced columns (FirstName, MiddleName, LastName, EmailAddress, CompanyID, IsDelete); or the dbo.ClientName function doesn't exist, or is not accessible; or there is an error in the dbo.ClientName function; or your row doesn't contain a Client# cell; or the Client# cell contains an unexpected value.

Without seeing your database and the actual query you're trying to execute, we can't tell you precisely what the problem is.

However, removing the SQL Injection vulnerability is simple, and would eliminate the last possibility (an invalid value):

C#

const string query = "SELECT  RTRIM(dbo.ClientName(FirstName,MiddleName,LastName)) + ',' + EmailAddress As Contact FROM  Contacts WHERE CompanyID = {0} And (IsDelete Is Null Or IsDelete = 0)";

object companyID = ((System.Windows.Forms.DataGridViewComboBoxCell)grvJobList.Rows[grvJobList.CurrentRow.Index].Cells["Client#"]).Value;

DataGridViewComboBoxCell ContactCmb = new DataGridViewComboBoxCell();

using (EFDbContext db = new EFDbContext())
{
	var contacts = db.Database.SqlQuery<string>(query, companyID);
	ContactCmb.DataSource = contacts.ToList();
}

EDIT: Based on the exception message, the problem is with the ValueMember and DisplayMember properties on your column. These point to properties on the items within the data source collection. But the items are simple string values, which won't have a property called Contact.

Probably the simplest option is to create a class to represent the data:

C#

public sealed class ContactName
{
    public string Contact { get; set; }
}

Then use that class in your query:

C#

using (EFDbContext db = new EFDbContext())
{
	var contacts = db.Database.SqlQuery<ContactName>(query, companyID);
	ContactCmb.DataSource = contacts.ToList();
}

ContactCmb.ValueMember = nameof(ContactName.Contact);
ContactCmb.DisplayMember = nameof(ContactName.Contact);