求教关于COMBO控件的使用

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*-- Form:         form1 (d:\documents\visual foxpro 项目\frmcombo.scx)
*-- ParentClass:  form
*-- BaseClass:    form
*-- Time Stamp:   02/25/23 11:45:01 AM
*
DEFINE CLASS form1 AS form


    Top = 0
    Left = 0
    Height = 455
    Width = 683
    DoCreate = .T.
    Caption = "Form1"
    Name = "Form1"


    ADD OBJECT combo1 AS combobox WITH ;
        ControlSource = "", ;
        Height = 24, ;
        Left = 20, ;
        Top = 20, ;
        Width = 100, ;
        Name = "Combo1"


    PROCEDURE combo1.KeyPress &&在combo控件上键入回车，则将combo键的值写入控制数据源
        LPARAMETERS nKeyCode, nShiftAltCtrl
        IF nkeycode=13
            SELECT table2
            GO TOP
            LOCATE FOR ALLTRIM(field2)=ALLTRIM(this.Value)
            IF FOUND() &&是数据源里的数据则添加，否则什么都不做
                SELECT table1
                INSERT INTO table1 (field1) VALUES (this.value)
                brow
            ENDIF
        ENDIF

    ENDPROC


    PROCEDURE combo1.Init
        ON ERROR cancel
        CREATE CURSOR table1 (field1 c(10))
        this.ControlSource="table1"
        CREATE cursor table2 (field2 c(10))
        SELECT table2
        INSERT INTO table2 (field2) VALUES ("aaa")
        INSERT INTO table2 (field2) VALUES ("bbb")
        INSERT INTO table2 (field2) VALUES ("ccc")
        this.RowSourceType = 2
        this.RowSource="table2"
    ENDPROC


    PROCEDURE combo1.DblClick &&在combo控件上双击时调用keypress事件
        this.KeyPress(13)
    ENDPROC


ENDDEFINE
*
*-- EndDefine: form1
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