c#中利用委托反射将DataTable转换为实体集的代码

类泛型的约束：

public static class tomodel<t> where t : class, new()

定义委托：

public delegate void setstring(string value);

创建委托方法：

private static setstring createstringdelegate(t model, string propertyname)
{
methodinfo mi = model.gettype().getproperty(propertyname).getsetmethod();
type type = typeof(setstring);
return delegate.createdelegate(type, model, mi) as setstring;
}

利用反射和委托将datatable转换为实体集：

public static ilist<t> getdelegate_tomodellist(datatable dt)
{
ilist<t> list = new list<t>();
if (dt == null || dt.rows.count < 1) return list;
setstring setdelegatestring;
foreach (datarow dr in dt.rows)
{
t model = new t();
foreach (datacolumn dc in dt.columns)
{
setdelegatestring = createstringdelegate(model, dc.columnname);
setdelegatestring(dr[dc.columnname].tostring());
}
list.add(model);
}
return list;
}

这样写问题就来了，因为委托定义的参数时string类型的，因为我们实体中可能有int或者datetime类型的，这时就需要用上泛型委托了
如果这样定义委托：

public delegate void setstring<pt>(pt value)

创建委托方法（这里有问题，不知如何处理）：

private static setstring createstringdelegate(t model, string propertyname)
{
methodinfo mi = model.gettype().getproperty(propertyname).getsetmethod();
type type = typeof(model).getproperty(propertyname).propertytype;
return delegate.createdelegate(type, model, mi) as setstring<type>;
}

利用反射和委托将datatable转换为实体集：

public static ilist<t> getdelegate_tomodellist(datatable dt)
{
ilist<t> list = new list<t>();
if (dt == null || dt.rows.count < 1) return list;
foreach (datarow dr in dt.rows)
{
t model = new t();
foreach (datacolumn dc in dt.columns)
{
setstring<typeof(t).getproperty(dc.columnname).propertytype> setdelegatestring = createstringdelegate(model, dc.columnname);
setdelegatestring(dr[dc.columnname].tostring());
}
list.add(model);
}
return list;
}

一直疑惑着，希望有人帮我解决疑惑，直接反射的方法我也有，但是这个问题不解决，心里一直有疙瘩，希望有人帮帮忙，谢谢
泛型可以动态构建的，你了解了这个，就能解决了，附上我的简略代码：

using system;
using system.collections.generic;
using system.linq;
using system.text;
using system.data;
using system.reflection;
namespace rfttomodel {
class program {
static void main(string[] args) {
var result = tomodel<testmodel>.getdelegate_tomodellist(buildsampletable());
foreach (var item in result) {
console.writeline(item);
}
console.read();
}
static datatable buildsampletable() {
datatable result = new datatable();
result.columns.add("id", typeof(int));
result.columns.add("name", typeof(string));
result.columns.add("isdeleted", typeof(bool));
result.rows.add(new object[] { 1, "m.k", false });
result.rows.add(new object[] { 2, "b.g", true });
return result;
}
}
public class testmodel {
public int id { get; set; }
public string name { get; set; }
public bool isdeleted { get; set; }
public override string tostring() {
return string.format("id:{0} name:{1} isdeleted:{2}", id, name, isdeleted);
}
}
public delegate void setvalue<t>(t value);
public static class tomodel<t> where t : class, new() {
private static delegate createsetdelegate(t model, string propertyname) {
methodinfo mi = model.gettype().getproperty(propertyname).getsetmethod();
//这里构造泛型委托类型
type deltype = typeof(setvalue<>).makegenerictype(getpropertytype(propertyname));
return delegate.createdelegate(deltype, model, mi);
}
private static type getpropertytype(string propertyname) {
return typeof(t).getproperty(propertyname).propertytype;
}
public static ilist<t> getdelegate_tomodellist(datatable dt) {
ilist<t> list = new list<t>();
if (dt == null || dt.rows.count < 1) return list;
delegate setdelegate;
foreach (datarow dr in dt.rows) {
t model = new t();
foreach (datacolumn dc in dt.columns) {
setdelegate = createsetdelegate(model, dc.columnname);
//这里改变类型
setdelegate.dynamicinvoke(convert.changetype(dr[dc.columnname], getpropertytype(dc.columnname)));
}
list.add(model);
}
return list;
}
}
}

谢谢，我刚修改了，我传进去sqldatareader和datatable都可以转换了，当时只想着每次返回一个特定类型等委托都不知道如何下手，看着你的方法解决了
没想到dynamicinvoke这个方法，算是学习了，你的代码写着层次好清晰，看了是一种享受，向你学习啊！