📄 deletingrecords.htm

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<span style="font-family:Helvetica,Arial; font-size:12pt; color:#000000"><b>Deleting Records
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Use the <a href=tdataset_delete.htm>Delete </a>method to delete the current record in an active dataset.When the <i>Delete</i> method is called,
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><font face="Symbol" size="2" color="#000000">&#183;</font></span></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">The dataset receives a <i>BeforeDelete</i> event.
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</span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><font face="Symbol" size="2" color="#000000">&#183;</font></span></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">The dataset attempts to delete the current record.
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</span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><font face="Symbol" size="2" color="#000000">&#183;</font></span></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">The dataset returns to the <i>dsBrowse</i> state.
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</span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><font face="Symbol" size="2" color="#000000">&#183;</font></span></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">The dataset receives an <i>AfterDelete</i> event.
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If want to prevent the deletion in the <i>BeforeDelete</i> event handler, you can call the global <i>Abort</i> procedure:
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</span><span style="font-family:Courier New; font-size:8pt; color:#000000"><b>procedure</b>&nbsp;TForm1.TableBeforeDelete&nbsp;(Dataset:&nbsp;TDataset)<b>begin</b>
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&nbsp;&nbsp;<b>if</b>&nbsp;MessageDlg(<span style="font-family:Courier New; font-size:8pt; color:#000080">'Delete&nbsp;This&nbsp;Record?'</span></span><span style="font-family:Courier New; font-size:8pt; color:#000000">,&nbsp;mtConfirmation,&nbsp;mbYesNoCancel,&nbsp;<span style="font-family:Courier New; font-size:8pt; color:#000080">0</span></span><span style="font-family:Courier New; font-size:8pt; color:#000000">)&nbsp;&lt;&gt;&nbsp;mrYes&nbsp;<b>then</b>
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&nbsp;&nbsp;&nbsp;&nbsp;Abort;
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<b>end</b>;
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If <i>Delete</i> fails, it generates an <i>OnDeleteError</i> event. If the <i>OnDeleteError </i>event handler can't correct the problem, the dataset remains in <i>dsEdit</i> state. If <i>Delete</i> succeeds, the dataset reverts to the <i>dsBrowse</i> state and the record that followed the deleted record becomes the current record.
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If you provide a navigator component on your forms, users can delete the current record by clicking the navigator's Delete button. In code, you must call <i>Delete</i> explicitly to remove the current record.
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