反射應(yīng)用之一：根據(jù)控件名、屬性名進(jìn)行取值和賦值
2024-07-21 02:17:06
供稿：網(wǎng)友
'必須引用命名空間system.reflection,system.componentmodel
'以下根據(jù)控件名和屬性名取值
public function getvaluecontrolproperty(byval classinstance as object, byval controlname as string, byval propertyname as string) as object
dim result as object
dim mytype as type = classinstance.gettype
dim myfieldinfo as fieldinfo = mytype.getfield("_" & controlname, bindingflags.nonpublic or _
bindingflags.instance or bindingflags.public or bindingflags.instance)
if not myfieldinfo is nothing then
dim properties as propertydescriptorcollection = typedescriptor.getproperties(mytype)
dim myproperty as propertydescriptor = properties.find(propertyname, false)
if not myproperty is nothing then
dim ctr as object
ctr = myfieldinfo.getvalue(classinstance)
try
result = myproperty.getvalue(ctr)
catch ex as exception
msgbox(ex.message)
end try
end if
end if
return result
end function
'以下根據(jù)控件名和屬性名賦值
public function setvaluecontrolproperty(byval classinstance as object, byval controlname as string, byval propertyname as string, byval value as object) as object
dim result as object
dim mytype as type = classinstance.gettype
dim myfieldinfo as fieldinfo = mytype.getfield("_" & controlname, bindingflags.nonpublic _
or bindingflags.instance or bindingflags.public or bindingflags.instance) '加"_"這個(gè)是特要緊的
if not myfieldinfo is nothing then
dim properties as propertydescriptorcollection = typedescriptor.getproperties(mytype)
dim myproperty as propertydescriptor = properties.find(propertyname, false) '這里設(shè)為true就不用區(qū)分大小寫了
if not myproperty is nothing then
dim ctr as object
ctr = myfieldinfo.getvalue(classinstance) '取得控件實(shí)例
try
myproperty.setvalue(ctr, value)
result = ctr
catch ex as exception
msgbox(ex.message)
end try
end if
end if
return result
end function
'調(diào)用
'以下實(shí)現(xiàn)label1.text=textbox1.text,label2.text=textbox2
private sub button1_click(byval sender as system.object, byval e as system.eventargs) handles button1.click
dim i as integer
for i = 1 to 2
me.setvaluecontrolproperty(me, "label" & i.tostring, "text", getvaluecontrolproperty(me, "textbox" & i.tostring, "text"))
next i
end sub
