Activator.CreateInstance 方法 (Type)和Class1 obj=new Class1()方法实例化

需要动态的创建一个实例模型的时候，就用Activator.CreateInstance(Type type);

 

如果是明确的知道要创建哪个实例的模型，就可以用 new Class1()了。

也可以通过程序集Assembly.CreateInstance()来创建，不过其实程序集创建也是调用的Activator.CreateInstance(Type type)。

代码

   
     

    
      
    
      public
    
       
    
      static
    
       
    
      object
    
       GetFromDataTable(DataTable dt, Type objectType, 
    
      int
    
       row)
 {
 
    
      if
    
       (dt 
    
      ==
    
       
    
      null
    
      )
 {
 
    
      return
    
       
    
      null
    
      ;
 }
 
    
      if
    
       (dt.Rows.Count 
    
      <=
    
       row)
 {
 
    
      return
    
       
    
      null
    
      ;
 }

 
    
      object
    
       obj 
    
      =
    
       Activator.CreateInstance(objectType);

 PropertyInfo[] props 
    
      =
    
       objectType.GetProperties(BindingFlags.Public 
    
      |
    
       BindingFlags.Instance);

 
    
      foreach
    
       (DataColumn dc 
    
      in
    
       dt.Columns)
 {
 
    
      foreach
    
       (PropertyInfo p 
    
      in
    
       props)
 {
 
    
      if
    
       (p.Name.Equals(dc.ColumnName, StringComparison.OrdinalIgnoreCase))
 {
 
    
      if
    
       (
    
      !
    
      dt.Rows[row].IsNull(dc.ColumnName))
 {
 
    
      object
    
       destObj 
    
      =
    
       dt.Rows[row][dc.ColumnName];

 
    
      bool
    
       succ 
    
      =
    
       
    
      false
    
      ;

 
    
      if
    
       (p.PropertyType 
    
      ==
    
       destObj.GetType())
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 }
 
    
      else
    
      
 {
 
    
      if
    
       (p.PropertyType 
    
      ==
    
       
    
      typeof
    
      (
    
      int
    
      ))
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 
    
      int
    
       tmpInt 
    
      =
    
       
    
      0
    
      ;
 
    
      int
    
      .TryParse(destObj.ToString(), 
    
      out
    
       tmpInt);
 destObj 
    
      =
    
       tmpInt;
 }
 
    
      else
    
       
    
      if
    
       (p.PropertyType 
    
      ==
    
       
    
      typeof
    
      (
    
      long
    
      ))
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 
    
      long
    
       tmpLong 
    
      =
    
       
    
      0
    
      ;
 
    
      long
    
      .TryParse(destObj.ToString(), 
    
      out
    
       tmpLong);
 destObj 
    
      =
    
       tmpLong;
 }
 
    
      else
    
       
    
      if
    
       (p.PropertyType 
    
      ==
    
       
    
      typeof
    
      (
    
      bool
    
      ))
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 
    
      bool
    
       tmpBool 
    
      =
    
       
    
      false
    
      ;
 
    
      bool
    
      .TryParse(destObj.ToString(), 
    
      out
    
       tmpBool);
 destObj 
    
      =
    
       tmpBool;
 }
 
    
      else
    
       
    
      if
    
       (p.PropertyType 
    
      ==
    
       
    
      typeof
    
      (DateTime))
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 DateTime tmpDateTime;
 DateTime.TryParse(destObj.ToString(), 
    
      out
    
       tmpDateTime);
 destObj 
    
      =
    
       tmpDateTime;
 }
 
    
      else
    
       
    
      if
    
       (p.PropertyType 
    
      ==
    
       
    
      typeof
    
      (
    
      float
    
      ))
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 
    
      float
    
       tmpFloat;
 
    
      float
    
      .TryParse(destObj.ToString(), 
    
      out
    
       tmpFloat);
 destObj 
    
      =
    
       tmpFloat;
 }
 
    
      else
    
       
    
      if
    
       (p.PropertyType 
    
      ==
    
       
    
      typeof
    
      (
    
      decimal
    
      ))
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 
    
      decimal
    
       tmpDecimal;
 
    
      decimal
    
      .TryParse(destObj.ToString(), 
    
      out
    
       tmpDecimal);
 destObj 
    
      =
    
       tmpDecimal;
 }
 
    
      else
    
       
    
      if
    
       (p.PropertyType 
    
      ==
    
       
    
      typeof
    
      (
    
      double
    
      ))
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 
    
      double
    
       tmpDouble;
 
    
      double
    
      .TryParse(destObj.ToString(), 
    
      out
    
       tmpDouble);
 destObj 
    
      =
    
       tmpDouble;
 }
 
    
      else
    
       
    
      if
    
       (p.PropertyType 
    
      ==
    
       
    
      typeof
    
      (
    
      char
    
      ))
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 
    
      char
    
       tmpChar;
 
    
      char
    
      .TryParse(destObj.ToString(), 
    
      out
    
       tmpChar);
 destObj 
    
      =
    
       tmpChar;
 }
 
    
      else
    
       
    
      if
    
       (p.PropertyType 
    
      ==
    
       
    
      typeof
    
      (Int16))
 {
 succ 
    
      =
    
       
    
      true
    
      ;
 Int16 tmpInt16;
 Int16.TryParse(destObj.ToString(), 
    
      out
    
       tmpInt16);
 destObj 
    
      =
    
       tmpInt16;
 }
 
    
      else
    
      
 {
 succ 
    
      =
    
       
    
      false
    
      ;
 }
 }
 
    
      if
    
      (succ)
 {
 p.SetValue(obj, destObj, 
    
      null
    
      );
 }
 }
 }
 }
 }

 
    
      return
    
       obj;
 }