Difference between revisions of "ConstructorInfo"

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{{ClassBox
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| super=[[MemberInfo]]
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| platform=all
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| scope=global
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}}
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{{Description
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|text=Contains information about the constructors for a class via the [[Introspection]] system.
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}}
  
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<dynamicTable id="Properties" super="MemberInfo" class="propertyTable" title="Properties" columns="3">
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</dynamicTable>
  
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=='''Description'''==
 
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Contains information about the constructors for a class via the [[Introspection|Introspection]] system.
 
  
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<dynamicTable id="Methods" super="MemberInfo" class="methodTable" title="Methods" columns="3">
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{{Method | name=GetParameters | description=GetParameters() as ParameterInfo()&#x0A;Returns an array of ParameterInfo items }}
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{{Method | name=Invoke | params=[params() as [[Variant]]]  | returntype=Datatype of the object being instantiated. | modifiedinversion=2008r2 | description=Invoke([params() as Variant] ) as Datatype of the object being instantiated.&#x0A;Invokes the constructor }}
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</dynamicTable>
  
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== Sample Code ==
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This code uses the Invoke method to call the FolderItem constructor that takes no parameters:
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<rbcode>
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Var ti As Introspection.TypeInfo = GetTypeInfo(FolderItem)
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Var ci() As Introspection.ConstructorInfo = ti.GetConstructors
  
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=='''Super Class'''==
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Var f As FolderItem
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[[MemberInfo|MemberInfo]]
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f = ci(0).Invoke
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</rbcode>
  
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=='''Properties'''==
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==See Also==
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[[Introspection]] module; [[AttributeInfo]], [[MemberInfo]], [[MethodInfo]], [[ObjectIterator]], [[ParameterInfo]], [[PropertyInfo]], [[TypeInfo]] classes; [[GetTypeInfo]] function.
  
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{| cellpadding="8" cellspacing="0" border="1"
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[http://developer.xojo.com/xojo-introspection-constructorinfo Xojo.Introspection.ConstructorInfo]
  
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! width=10%  style="background-color:#e0e0e0" | Name
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[[Category:Language_Classes]]
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[[Category:Language_Introspection]]
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! width=15%  style="background-color:#e0e0e0" | Type
 
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! width=55%  style="background-color:#e0e0e0" | Description
 
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|-
 
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|ReturnType
 
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|[[TypeInfo|TypeInfo]]
 
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|If the constructor returns a value, this is the datatype of the returned value. If the method does not return a value, ReturnType is [[Nil|Nil]].
 
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|-
 
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|}
 
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=='''Methods'''==
 
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{| cellpadding="8" cellspacing="0" border="1"
 
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! width=10%  style="background-color:#e0e0e0" | Name
 
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! width=20%  style="background-color:#e0e0e0" | Parameters
 
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! width=25%  style="background-color:#e0e0e0" | Return Type
 
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! width=55%  style="background-color:#e0e0e0" | Description
 
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|-
 
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|GetParameters
 
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|
 
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|[[ParameterInfoList|ParameterInfo()]]
 
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|Returns an array of [[ParameterInfo|ParameterInfo]] items. Use GetParameters to obtain datatype information on the constructor's parameters.
 
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|-
 
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|<div style="font-style:italic; color:green;">Changed 2008r2</div>Invoke
 
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|[params() as [[Variant|Variant]]]
 
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|Datatype of the object being instantiated.
 
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|Invokes the constructor. Pass the optional array of variants for the constructor's parameter values, if any. You will get an [[OutOfBoundsException|OutOfBoundsException]] if the number of parameters does not match or an [[IllegalCastException|IllegalCastException]] if the types do not match.
 
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|-
 
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|}
 
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=='''Examples'''==
 
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This example gets the '''ConstructorInfo''' for the [[FolderItem|FolderItem]] class. The Invoke method is used to create a new instance based on the constructor that takes no parameters.
 
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<div style="background-color:#d0d0d0; padding-left:30px">[[Dim|Dim]] ti as [[Introspection|Introspection]].[[TypeInfo|Typeinfo]]=[[GetTypeInfo|GetTypeinfo]]([[FolderItem|FolderItem]])
 
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<br /></div>
 
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<div style="background-color:#d0d0d0; padding-left:30px">[[Dim|Dim]] ci() as [[Introspection|Introspection]].ConstructorInfo=ti.GetConstructors
 
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<br /></div>
 
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<div style="background-color:#d0d0d0; padding-left:30px"><br /></div>
 
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<div style="background-color:#d0d0d0; padding-left:30px">[[Dim|Dim]] f as [[FolderItem|FolderItem]]<br /></div>
 
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<div style="background-color:#d0d0d0; padding-left:30px">f=ci(0).Invoke
 
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<br /></div>
 
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=='''See Also'''==
 
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[[Introspection|Introspection]] module; [[AttributeInfo|AttributeInfo]], [[MemberInfo|MemberInfo]], [[MethodInfo|MethodInfo]], [[ObjectIterator|ObjectIterator]], [[ParameterInfo|ParameterInfo]], [[PropertyInfo|PropertyInfo]], [[TypeInfo|TypeInfo]] classes; [[GetTypeInfo|GetTypeInfo]] function.
 
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[[Category:Classes]]
 
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[[Category:Introspection]]
 

Latest revision as of 21:03, 28 January 2021

Class (inherits from MemberInfo)

Contains information about the constructors for a class via the Introspection system.

Properties
IsPrivate fa-lock-32.png IsPublic fa-lock-32.png
IsProtected fa-lock-32.png Name fa-lock-32.png


Methods
GetAttributes GetParameters Invoke

Sample Code

This code uses the Invoke method to call the FolderItem constructor that takes no parameters:

Var ti As Introspection.TypeInfo = GetTypeInfo(FolderItem)
Var ci() As Introspection.ConstructorInfo = ti.GetConstructors

Var f As FolderItem
f = ci(0).Invoke

See Also

Introspection module; AttributeInfo, MemberInfo, MethodInfo, ObjectIterator, ParameterInfo, PropertyInfo, TypeInfo classes; GetTypeInfo function.

Xojo.Introspection.ConstructorInfo

Retrieved from "http://docs.xojo.com/index.php?title=ConstructorInfo&oldid=76888"