引发自定义控件LoadPostData方法的必要条件!-ASP教程,数据库相关

自定义控件要引发loadpostdata方法，需要包含一个id为this.uniqueid的控件

可在控件组中加入一个hidden控件!

writer.write("<input type=hidden name=" + me.uniqueid + ">")

或者干脆更简单的做法，把submit的name属性设置为me.uniqueid

imports system.componentmodel

imports system.web.ui

imports system.web.ui.webcontrols

<defaultproperty("text"), toolboxdata("<{0}:login runat=server></{0}:login>")> public class login

inherits system.web.ui.webcontrols.webcontrol

implements ipostbackdatahandler

public event checkerror as eventhandler

private _user as string

private _pass as string

public function loadpostdata(byval postdatakey as string, byval postcollection as system.collections.specialized.namevaluecollection) as boolean implements system.web.ui.ipostbackdatahandler.loadpostdata

_user = ctype(postcollection(me.uniqueid & ":user"), string)

_pass = ctype(postcollection(me.uniqueid & ":pass"), string)

if _user <> _pass then

return true

else

return false

end if

end function

public sub raisepostdatachangedevent() implements system.web.ui.ipostbackdatahandler.raisepostdatachangedevent

oncheckerror()

end sub

public sub oncheckerror()

raiseevent checkerror(me, new system.eventargs())

end sub

protected overrides sub render(byval writer as system.web.ui.htmltextwriter)

writer.renderbegintag(htmltextwritertag.table)

writer.renderbegintag(htmltextwritertag.tr)

writer.renderbegintag(htmltextwritertag.td)

writer.write("用户名：")

writer.renderendtag()

writer.renderbegintag(htmltextwritertag.td)

writer.addattribute(htmltextwriterattribute.type, "textbox")

writer.addattribute(htmltextwriterattribute.name, me.uniqueid & ":user")

writer.addattribute(htmltextwriterattribute.maxlength, "30")

writer.renderbegintag(htmltextwritertag.input)

writer.renderendtag()

writer.renderendtag()

writer.renderendtag()

writer.renderbegintag(htmltextwritertag.tr)

writer.renderbegintag(htmltextwritertag.td)

writer.write("密码：")

writer.renderendtag()

writer.renderbegintag(htmltextwritertag.td)

writer.addattribute(htmltextwriterattribute.type, "password")

writer.addattribute(htmltextwriterattribute.name, me.uniqueid & ":pass")

writer.addattribute(htmltextwriterattribute.maxlength, "30")

writer.renderbegintag(htmltextwritertag.input)

writer.renderendtag()

writer.renderendtag()

writer.renderendtag()

writer.renderbegintag(htmltextwritertag.tr)

writer.addattribute(htmltextwriterattribute.cols, "2")

writer.renderbegintag(htmltextwritertag.td)

writer.addattribute(htmltextwriterattribute.type, "submit")

writer.addattribute(htmltextwriterattribute.name, me.uniqueid)

writer.addattribute(htmltextwriterattribute.value, "提交")

writer.renderbegintag(htmltextwritertag.input)

writer.renderendtag()

writer.renderendtag()

writer.renderendtag()

writer.renderendtag()

end sub

end class