• Delphi ClientDataSet 排序[1]


    Delphi ClientDataSet 排序[1] 

    1、单个字段排序 (索引名称自定义,例如:sSort)

    //升序
    with ClientDataSet1  do
    begin
      IndexDefs.Update;   //更新
      if IndexDefs.IndexOf( 'sSort' )>=0 then DeleteIndex('sSort');   //删除索引
      AddIndex('sSort',Column.FieldName, [ixPrimary], Column.FieldName );   //添加索引  升序
      IndexName:= 'sSort';  //索引
      First;   //回到第一行
    end;
    
    //降序  ixDescending
    with ClientDataSet1  do
    begin
      IndexDefs.Update;
      if  IndexDefs.IndexOf( 'sSort' )>=0 then DeleteIndex('sSort');
      AddIndex('sSort',Column.FieldName,[ixDescending],Column.FieldName);   
      IndexName:='sSort';
      First;
    end;

    2、多个排序字段 (例如:Field1,Field2)

    with ClientDataSet1  do
    begin
      IndexDefs.Update;
       if  IndexDefs.IndexOf( 'sSort' )>=0 then DeleteIndex( 'sSort' );
      AddIndex('sSort','Field1, Field2',[],'');
      IndexName:='sSort';
      First;
    end;
    
    with ClientDataSet1  do
    begin
      IndexDefs.Update;
      if IndexDefs.IndexOf( 'sSort' )>=0 then DeleteIndex( 'sSort' );
      AddIndex('sSort','Field1,Field2',[],'Field1, Field2');
      IndexName:='sSort' ;
      First;
    end;
    

    TIndexOption参数取值:

    TIndexOption = (
            ixPrimary,      //初级  升序
             ixUnique,      //唯一值
            ixDescending,   //降序
            ixCaseInsensitive,  //不区分大小写
            ixExpression,    //表达式
            ixNonMaintained  //不保持
    );
      TIndexOptions = set of TIndexOption;    
    

      

      

      

    创建时间:2021.01.25  更新时间:

    博客园 滔Roy https://www.cnblogs.com/guorongtao 希望内容对你所有帮助,谢谢!
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  • 原文地址:https://www.cnblogs.com/guorongtao/p/14325422.html
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