[求助]我在用searchexpression时的问题？

<P>我在查找时，明明属性数据库中有的数据为什么用searchexpression查不出来？</P>
<P>比如：</P>
<P>Set recs =map1.Layers(0).SearchExpression(Text1.text)</P>
<P>结果出来，没有记录，怎么回事？</P>
<img src="images/post/smile/dvbbs/em08.gif" /><img src="images/post/smile/dvbbs/em08.gif" />

<P>首先，查询表达式要正确，例如：</P>
<P>Private Sub Command1_Click()</P>
<P>Dim moRecset As MapObjects2.Recordset<BR>Dim recSelection As MapObjects2.Recordset</P>
<P>Dim Poly As New MapObjects2.Polygon</P>
<P>Dim Poly1 As New MapObjects2.Polygon</P>
<P>Set moRecset= Nothing'清空数据集</P>
<P>Set moRecset = Map1.Layers("country").Records</P>
<P>Dim Expression As String</P>
<P>'查询字符型moRecset是表示记录集，后面会提到，Fields表示字段,Name表示字段名</P>
<P>If moRecset.Fields("Name").Type = moString Then</P>
<P>Expression = "CNTRY_NAME = 'China' "  '注意，字符是单引号</P>
<P>Else</P>
<P><BR>Expression = "ID=0"</P>
<P>End If</P>
<P>'recSelection 为选择记录集赋值 </P>
<P>  Set recSelection = Map1.Layers("country").SearchExpression(Expression)<BR>  If recSelection.EOF Then '判断recSelection不为空<BR>   MsgBox "您所查找的信息不存在，请核对你的输入", vbOKOnly, "温馨的提示您!"</P>
<P>Exit sub<BR>  End If<BR>  recSelection.MoveFirst' 移动到首记录<BR>  Do While Not recSelection.EOF</P>
<P>'获得找到记录的空间位置，SHAPE表示要素</P>
<P>  Set Poly = recSelection.Fields("Shape").Value <BR>  recSelection.MoveNext 移动到下一条记录<BR><BR>   For i = 0 To Poly.Parts.Count - 1<BR>     Poly1.Parts.Add Poly.Parts(i)  'Poly1用于多项查询,将查询到的对象一起显示<BR>   Next<BR>  Loop<BR>  Map1.FlashShape Poly1, 3 '闪烁Poly1<BR>  Map1.TrackingLayer.Refresh (True)<BR>  Set Poly1 = Nothing</P>
<P>End Sub</P>

<P>假如写成recs=map1.layers(0).searchexpression("名称＝text1.text")应该符合ＳＱＬ要求了吧，为什么总是说＂要求对象＂呢？</P>

<img src="images/post/smile/dvbbs/em06.gif" /><img src="images/post/smile/dvbbs/em05.gif" />

<P>谢谢大家，解决了该问题。</P>

<P>recs.count=-1并不表示没有记录返回</P><P>你可以看看mo的参考里面对count这个属性有详细的解释</P><P>The Count property may return a value of -1 when the object is a Recordset derived from sources which do not contain header information such as:</P><P>1.an SDE layer
2.a Table object
3.a SearchExpression</P><P>In these cases, to obtain the correct Count of the Recordset, a Statistics object should be created from the Recordset, and the number of records taken from the Count property of this Statistics object.</P>

text1.text通常是个数值吧，但是serachExpression后面的参数是个表达式,如：id>100

<P>你加上 order by 应该就可以了的 </P><P> field = '2'  order by field  </P>

是没有记录，recs.count=-1, 现在还没有解决！

recs.Eof为真还是为假？