Search For Value or NULL

Business Logic Framework - How To:

Assuming that you would like to search for all customers whose email address contains 'a' or the email is null, the following code snippet shows how to achieve this:

Please note that the following code shows "Email" field being used. The QO_SHOP database schema does not contain the Email field, but it is added in one of the tutorials showing how to update the classes when the database schema is modified.

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using (Customers customer = new Customers())  

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{  

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    // Let the object know that you intend to perform a search by setting the ObjectMode property to ObjectModes.Search  

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    customer.ObjectMode = Akal.QuickObjects.ObjectBase.ObjectModes.Search;  

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    // PartialTextMatch property indicates that we would like the business object to perform partial text search.  

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    // This can be overridden or set at the field level as well.  

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    customer.PartialTextMatch = true;  

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    // Assign the value we would like to search for.  

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    customer.Email.Value = "a";  

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    // Change the SearchMode property to SearchModes.ValueOrNull and the business object will automatically search for  

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    // either the value OR a NULL in the email field.  

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    customer.Email.SearchMode = Akal.QuickObjects.ObjectBase.SearchModes.ValueOrNull;  

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    // For the above line to work correctly we must set the IsNull property to true.  

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    customer.Email.IsNull = true;  

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    this.GridView.DataSource = customer.Find();  

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    this.GridView.DataMember = customer.GetResultSetName();  

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}  

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Using customer As New Customers()   

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    ' Let the object know that you intend to perform a search by setting the ObjectMode property to ObjectModes.Search   

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    customer.ObjectMode = Akal.QuickObjects.ObjectBase.ObjectModes.Search   

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    ' PartialTextMatch property indicates that we would like the business object to perform partial text search.   

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    ' This can be overridden or set at the field level as well.   

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    customer.PartialTextMatch = True   

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    ' Assign the value we would like to search for.   

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    customer.Email.Value = "a"   

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    ' Change the SearchMode property to SearchModes.ValueOrNull and the business object will automatically search for   

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    ' either the value OR a NULL in the email field.   

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    customer.Email.SearchMode = Akal.QuickObjects.ObjectBase.SearchModes.ValueOrNull   

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    ' For the above line to work correctly we must set the IsNull property to true.   

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    customer.Email.IsNull = True   

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    Me.GridView.DataSource = customer.Find()   

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    Me.GridView.DataMember = customer.GetResultSetName()   

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End Using

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1	using (Customers customer = new Customers())
2	{
3	// Let the object know that you intend to perform a search by setting the ObjectMode property to ObjectModes.Search
4	customer.ObjectMode = Akal.QuickObjects.ObjectBase.ObjectModes.Search;
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7	// PartialTextMatch property indicates that we would like the business object to perform partial text search.
8	// This can be overridden or set at the field level as well.
9	customer.PartialTextMatch = true;
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12	// Assign the value we would like to search for.
13	customer.Email.Value = "a";
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15	// Change the SearchMode property to SearchModes.ValueOrNull and the business object will automatically search for
16	// either the value OR a NULL in the email field.
17	customer.Email.SearchMode = Akal.QuickObjects.ObjectBase.SearchModes.ValueOrNull;
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20	// For the above line to work correctly we must set the IsNull property to true.
21	customer.Email.IsNull = true;
22	this.GridView.DataSource = customer.Find();
23	this.GridView.DataMember = customer.GetResultSetName();
24	}
25

1	Using customer As New Customers()
2	' Let the object know that you intend to perform a search by setting the ObjectMode property to ObjectModes.Search
3	customer.ObjectMode = Akal.QuickObjects.ObjectBase.ObjectModes.Search
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6	' PartialTextMatch property indicates that we would like the business object to perform partial text search.
7	' This can be overridden or set at the field level as well.
8	customer.PartialTextMatch = True
9
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11	' Assign the value we would like to search for.
12	customer.Email.Value = "a"
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14	' Change the SearchMode property to SearchModes.ValueOrNull and the business object will automatically search for
15	' either the value OR a NULL in the email field.
16	customer.Email.SearchMode = Akal.QuickObjects.ObjectBase.SearchModes.ValueOrNull
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19	' For the above line to work correctly we must set the IsNull property to true.
20	customer.Email.IsNull = True
21	Me.GridView.DataSource = customer.Find()
22	Me.GridView.DataMember = customer.GetResultSetName()
23	End Using