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POWPF INotifyPropertyChanged not allowing null value
 

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  1. POWPF INotifyPropertyChanged not allowing null value
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    <p>Using WPF and EF and new to both. I may use the wrong terminology. </p> <p>Using the EF wizard and code generators, I set up an EF using several tables, one of which is a lookup table.</p> <p>I set up a form with a datagrid for the user to edit items in this lookup table. An issue I'm having is that the user can edit a cell, then close the form, but the editing of the cell will not update the underlying SQL database. I researched INotifyPropertyChanged and it seemed to be what I needed.</p> <p>I implemented INotifyPropertyChanged to class bound to the datagrid. Before the implementation, the datagrid displayed all null values. After implementation, a message displays when the first null value is read that a nullable object must have a value.</p> <p>Code:</p> <pre><code> Public Property ProcedureName As String Get Return _ProcedureName End Get Set(value As String) _ProcedureName = value RaisePropertyChanged("ProcedureName") End Set End Property Private _ProcedureName As String </code></pre> <p>The exception occurs at "_ProcedureName = value".</p> <p>Entire class:</p> <pre><code>Imports System </code></pre> <p>Imports System.Collections.ObjectModel</p> <p>Partial Public Class tlkpProcedures_PartB Inherits PropertyChangedBase Public Property CPT As String Get Return _CPT End Get Set(value As String) _CPT = value RaisePropertyChanged("CPT") End Set End Property Private _CPT As String Public Property ProcedureName As String Get Return _ProcedureName End Get Set(value As String) _ProcedureName = value RaisePropertyChanged("ProcedureName") End Set End Property Private _ProcedureName As String</p> <pre><code>Public Property BillingAmount As Nullable(Of Decimal) Get Return _BillingAmount End Get Set(value As Nullable(Of Decimal)) _BillingAmount = value RaisePropertyChanged("BillingAmount") End Set End Property Private _BillingAmount As Decimal Public Property UniqueID As Integer Public Overridable Property tblBilling_PartB As ObservableCollection(Of tblBilling_PartB) = New ObservableCollection(Of tblBilling_PartB) </code></pre> <p>End Class</p> <p>Any help or advice is appreciated.</p>
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    1. USuser3014908
    1. USuser3014908
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    1. CODo you really think that anybody could work out what your problem is from that very basic description in just four lines? That's like going to a motor garage and saying 'My car won't start. It's red and has four wheels and windows. What's wrong with it?'
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      1. USSheridan
    2. COOk, my apologies. I've added more to my original post. Let me know if there's something else I need to post.
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    3. CODude... you should *always* read over your question *before* you post it... half of your class formatting is messed up. On this website, you have to add four spaces to the start of each line to tell the formatter to format that line as code. So add four spaces to the start of each line in your class and it should be ok. Where is the code that you use to update the EF tables?
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