Question

First off, I am new to programming (especially with C#) and thanks for your help.

I have a static web form with about 150 form objects (most checkboxes). I decided to go 1 record per form submission in the sql db. So, for example, question X has a choice of 5 checkboxes. Each of these 5 checkboxes has a column in the db.

I have the post page complete(working) and am building an edit page where I load the record and then populate the form.

How I am doing this is by passing a stored proc the id and then putting all the returned column values into the according object properties, then setting the asp control object to them.

An example of setting the asp controls to the selected value:

questionX.Items[0].Selected = selectedForm.questionX0
questionX.Items[1].Selected = selectedForm.questionX1
questionX.Items[2].Selected = selectedForm.questionX2

As you see, this is very tiresome since there are over 150 of these to do. Also, I just found out if the response is NULL then I get the error that it cant be converted to a string. So, I have added this line of code to get past it:

This is the part where I am populating the returned column values into the object properties (entity is the object):

if (!String.IsNullOrEmpty((string)reader["questionX0"].ToString()))
{entity.patientUnderMdTreatment = (string)reader["questionX0"];}

So, instead of having to add this if then statement 150+ times. There must be a way to do this more efficiently.

Answer 1

First of all, it seems that you are using string.IsNullOrEmpty(value), but this won’t check for the special DBNull value that is returned from databases when the data is null. You should use something more akin to value is DBNull.

The rest of your problem sounds complex, so please don’t be put off if my answer is complex too. Personally I would use custom attributes:

Declare a custom attribute

The following is a skeleton to give you the idea. You may want to use the “Attribute” code snippet in Visual Studio to find out more about how to declare these.

[AttributeUsage(AttributeTargets.Field, AllowMultiple = false)]
public sealed class QuestionColumnAttribute : Attribute
{
    public string ColumnName { get; private set; }
    public QuestionColumnAttribute(string columnName)
    {
        ColumnName = columnName;
    }
}

Use the custom attribute in the entity class

Where you declare your entity class, add this custom attribute to every field, for example where patientUnderMdTreatment is declared:

[QuestionColumn("questionX0")]
public string patientUnderMdTreatment;

Iterate over the fields

Instead of iterating over the columns in the reader, iterate over the fields. For each field that has a QuestionColumnAttribute on it, get the relevant column from the reader:

foreach (var field in entity.GetType().GetFields())
{
    var attributes = field.GetCustomAttributes(typeof(QuestionColumnAttribute), true);
    if (attributes.Length == 0)
        continue;

    object value = reader[attributes[0].ColumnName];
    if (!(value is DBNull))
        field.SetValue(entity, value.ToString());
}

For the first part of your question where you set the ASP controls, you can use a similar strategy iterating over the fields of selectedForm, and this is probably simpler because you don’t need a custom attribute — just take only the fields whose name starts with “questionX”.