改变下拉编辑框的宽度

 

 

  ComboBox1.Perform(CB_SETDROPPEDWIDTH, 200, 0);

 

下拉高度

ComboBox1.DropDownCount:=20;

 

 

 

 

 

 

{$externalsym cb_geteditsel}
  cb_geteditsel             = $ 0140;
   {$externalsym cb_limittext}
  cb_limittext              = $ 0141;
   {$externalsym cb_seteditsel}
  cb_seteditsel             = $ 0142;
   {$externalsym cb_addstring}
  cb_addstring              = $ 0143;
   {$externalsym cb_deletestring}
  cb_deletestring           = $ 0144;
   {$externalsym cb_dir}
  cb_dir                    = $ 0145;
   {$externalsym cb_getcount}
  cb_getcount               = $ 0146;
   {$externalsym cb_getcursel}
  cb_getcursel              = $ 0147;
   {$externalsym cb_getlbtext}
  cb_getlbtext              = $ 0148;
   {$externalsym cb_getlbtextlen}
  cb_getlbtextlen           = $ 0149;
   {$externalsym cb_insertstring}
  cb_insertstring           = $ 014a;
   {$externalsym cb_resetcontent}
  cb_resetcontent           = $ 014b;
   {$externalsym cb_findstring}
  cb_findstring             = $ 014c;
   {$externalsym cb_selectstring}
  cb_selectstring           = $ 014d;
   {$externalsym cb_setcursel}
  cb_setcursel              = $ 014e;
   {$externalsym cb_showdropdown}
  cb_showdropdown           = $ 014f;
   {$externalsym cb_getitemdata}
  cb_getitemdata            = $ 0150;
   {$externalsym cb_setitemdata}
  cb_setitemdata            = $ 0151;
   {$externalsym cb_getdroppedcontrolrect}
  cb_getdroppedcontrolrect = $ 0152;
   {$externalsym cb_setitemheight}
  cb_setitemheight          = $ 0153;
   {$externalsym cb_getitemheight}
  cb_getitemheight          = $ 0154;
   {$externalsym cb_setextendedui}
  cb_setextendedui          = $ 0155;
   {$externalsym cb_getextendedui}
  cb_getextendedui          = $ 0156;
   {$externalsym cb_getdroppedstate}
  cb_getdroppedstate        = $ 0157;
   {$externalsym cb_findstringexact}
  cb_findstringexact        = $ 0158;
   {$externalsym cb_setlocale}
  cb_setlocale              = 345;
   {$externalsym cb_getlocale}
  cb_getlocale              = 346;
   {$externalsym cb_gettopindex}
  cb_gettopindex            = 347;
   {$externalsym cb_settopindex}
  cb_settopindex            = 348;
   {$externalsym cb_gethorizontalextent}
  cb_gethorizontalextent    = 349;
   {$externalsym cb_sethorizontalextent}
  cb_sethorizontalextent    = 350;
   {$externalsym cb_getdroppedwidth}
  cb_getdroppedwidth        = 351;
   {$externalsym cb_setdroppedwidth}
  cb_setdroppedwidth        = 352;
   {$externalsym cb_initstorage}
  cb_initstorage            = 353;
   {$externalsym cb_msgmax}
  cb_msgmax                 = 354;

来自为知笔记(Wiz)