/// <summary>
/// Generates a dynamic method on the given type.
/// </summary>
private GetPropertyValuesInvoker GenerateGetPropertyValuesMethod(IGetter[] getters)
{
var methodArguments = new[] { typeof(object), typeof(GetterCallback) };
DynamicMethod method = CreateDynamicMethod(typeof(object[]), methodArguments);
ILGenerator il = method.GetILGenerator();
LocalBuilder thisLocal = il.DeclareLocal(typeOfThis);
LocalBuilder dataLocal = il.DeclareLocal(typeof(object[]));
// Cast the 'this' pointer to the appropriate type and store it in a local variable
il.Emit(OpCodes.Ldarg_0);
EmitCastToReference(il, mappedType);
il.Emit(OpCodes.Stloc, thisLocal);
// Allocate the values array and store it in a local variable
il.Emit(OpCodes.Ldc_I4, getters.Length);
il.Emit(OpCodes.Newarr, typeof(object));
il.Emit(OpCodes.Stloc, dataLocal);
//get all the data from the object into the data array to be returned
for (int i = 0; i < getters.Length; i++)
{
// get the member accessors
IGetter getter = getters[i];
// queue up the array storage location for the value
il.Emit(OpCodes.Ldloc, dataLocal);
il.Emit(OpCodes.Ldc_I4, i);
// get the value...
var optimizableGetter = getter as IOptimizableGetter;
if (optimizableGetter != null)
{
// using the getter's emitted IL code
il.Emit(OpCodes.Ldloc, thisLocal);
optimizableGetter.Emit(il);
EmitUtil.EmitBoxIfNeeded(il, getter.ReturnType);
}
else
{
// using the getter itself via a callback
MethodInfo invokeMethod = typeof(GetterCallback).GetMethod("Invoke",
new[] { typeof(object), typeof(int) });
il.Emit(OpCodes.Ldarg_1);
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldc_I4, i);
il.Emit(OpCodes.Callvirt, invokeMethod);
}
//store the value
il.Emit(OpCodes.Stelem_Ref);
}
// Return the data array
il.Emit(OpCodes.Ldloc, dataLocal.LocalIndex);
il.Emit(OpCodes.Ret);
return((GetPropertyValuesInvoker)method.CreateDelegate(typeof(GetPropertyValuesInvoker)));
}
/// <summary>
/// Generates a dynamic method on the given type.
/// </summary>
/// <returns></returns>
private SetPropertyValuesInvoker GenerateSetPropertyValuesMethod(IGetter[] getters, ISetter[] setters)
{
var methodArguments = new[] { typeof(object), typeof(object[]), typeof(SetterCallback) };
DynamicMethod method = CreateDynamicMethod(null, methodArguments);
ILGenerator il = method.GetILGenerator();
// Declare a local variable used to store the object reference (typed)
LocalBuilder thisLocal = il.DeclareLocal(typeOfThis);
il.Emit(OpCodes.Ldarg_0);
EmitCastToReference(il, mappedType);
il.Emit(OpCodes.Stloc, thisLocal.LocalIndex);
for (int i = 0; i < setters.Length; i++)
{
// get the member accessor
ISetter setter = setters[i];
System.Type valueType = getters[i].ReturnType;
var optimizableSetter = setter as IOptimizableSetter;
if (optimizableSetter != null)
{
// load 'this'
il.Emit(OpCodes.Ldloc, thisLocal);
// load the value from the data array
il.Emit(OpCodes.Ldarg_1);
il.Emit(OpCodes.Ldc_I4, i);
il.Emit(OpCodes.Ldelem_Ref);
EmitUtil.PreparePropertyForSet(il, valueType);
// using the setter's emitted IL
optimizableSetter.Emit(il);
}
else
{
// using the setter itself via a callback
MethodInfo invokeMethod = typeof(SetterCallback).GetMethod("Invoke",
new[] { typeof(object), typeof(int), typeof(object) });
il.Emit(OpCodes.Ldarg_2);
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldc_I4, i);
// load the value from the data array
il.Emit(OpCodes.Ldarg_1);
il.Emit(OpCodes.Ldc_I4, i);
il.Emit(OpCodes.Ldelem_Ref);
il.Emit(OpCodes.Callvirt, invokeMethod);
}
}
// Setup the return
il.Emit(OpCodes.Ret);
return((SetPropertyValuesInvoker)method.CreateDelegate(typeof(SetPropertyValuesInvoker)));
}
public static List <T> EmitToList <T>(this DataTable dt)
{
//确认参数有效
if (dt == null)
{
return(null);
}
List <T> list = new List <T>();
var objBuilder = EmitUtil.CreateBuilder(typeof(T));
for (int i = 0; i < dt.Rows.Count; i++)
{
//创建泛型对象
T _t = (T)objBuilder();
//获取对象所有属性
PropertyInfo[] propertyInfo = _t.GetType().GetProperties();
for (int j = 0; j < dt.Columns.Count; j++)
{
foreach (PropertyInfo info in propertyInfo)
{
//属性名称和列名相同时赋值
if (dt.Columns[j].ColumnName.ToUpper().Equals(info.Name.ToUpper()))
{
if (dt.Rows[i][j] != DBNull.Value)
{
info.SetValue(_t, dt.Rows[i][j], null);
}
else
{
info.SetValue(_t, null, null);
}
break;
}
}
}
list.Add(_t);
}
return(list);
}
private GetPropertyValueInvoker GenerateGetPropertyValueMethod(IGetter getter)
{
if (getter == null)
{
return(null);
}
if (!(getter is IOptimizableGetter optimizableGetter))
{
return(getter.Get);
}
var method = CreateDynamicMethod(typeof(object), new[] { typeof(object) });
var il = method.GetILGenerator();
// object (target) { (object) ((ClassType) target).GetMethod(); }
il.Emit(OpCodes.Ldarg_0);
EmitCastToReference(il, mappedType);
optimizableGetter.Emit(il);
EmitUtil.EmitBoxIfNeeded(il, getter.ReturnType);
il.Emit(OpCodes.Ret);
return((GetPropertyValueInvoker)method.CreateDelegate(typeof(GetPropertyValueInvoker)));
}
private SetPropertyValueInvoker GenerateSetPropertyValueMethod(ISetter setter)
{
if (setter == null)
{
return(null);
}
if (!(setter is IOptimizableSetter optimizableSetter))
{
return(setter.Set);
}
// void (target, value) { ((ClassType) target).SetMethod((FieldType) value); }
var method = CreateDynamicMethod(null, new[] { typeof(object), typeof(object) });
var il = method.GetILGenerator();
il.Emit(OpCodes.Ldarg_0);
EmitCastToReference(il, mappedType);
il.Emit(OpCodes.Ldarg_1);
EmitUtil.PreparePropertyForSet(il, optimizableSetter.Type);
optimizableSetter.Emit(il);
il.Emit(OpCodes.Ret);
return((SetPropertyValueInvoker)method.CreateDelegate(typeof(SetPropertyValueInvoker)));
}
public void GetNullableArg0_Test()
{
Assert.Equal(typeof(int), EmitUtil.GetNullableArg0(typeof(int?)));
Assert.Equal(typeof(float), EmitUtil.GetNullableArg0(typeof(float?)));
Assert.Equal(typeof(string), EmitUtil.GetNullableArg0(typeof(string)));
}
public void IsNullable_Test()
{
Assert.True(EmitUtil.IsNullable(typeof(int?)));
Assert.False(EmitUtil.IsNullable(typeof(string)));
}
