本文整理汇总了C#中System.Reflection.Emit.ILGenerator.EmitCheckHasValue方法的典型用法代码示例。如果您正苦于以下问题：C# ILGenerator.EmitCheckHasValue方法的具体用法？C# ILGenerator.EmitCheckHasValue怎么用？C# ILGenerator.EmitCheckHasValue使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类System.Reflection.Emit.ILGenerator的用法示例。
在下文中一共展示了ILGenerator.EmitCheckHasValue方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: GenerateFilterIl
public override void GenerateFilterIl(ILGenerator generator, Dictionary<string, string> filterValues, PropertyInfo property)
{
// Note: If the user specifies both true and false, we can skip this instance
string selection = filterValues["selection"];
string selectionLower = selection.ToLower();
bool selectionContainsTrue = selectionLower.Contains("true");
bool selectionContainsFalse = selectionLower.Contains("false");
bool selectionContainsNull = selectionLower.Contains("null");
Label lblReturnFalse = generator.DefineLabel();
Label lblCheckNextProperty = generator.DefineLabel();
generator.EmitCheckHasValue(property, nullableBoolStorage); // push 1 onto the stack if property has value; 0 if it is null.
generator.Emit(OpCodes.Pop);
// If the filter matches null, check if the value is null.
if (selectionContainsNull)
{
generator.EmitCheckHasValue(property, nullableBoolStorage);
generator.Emit(OpCodes.Brfalse, lblCheckNextProperty);
}
// If the property didn't match null and has no value, return false.
generator.EmitCheckHasValue(property, nullableBoolStorage);
generator.Emit(OpCodes.Brfalse, lblReturnFalse);
// From here on out, we assume the property has a value.
if (selectionContainsTrue)
{
generator.EmitGetValueFromNullableProperty(property, nullableBoolStorage);
generator.Emit(OpCodes.Brtrue, lblCheckNextProperty);
}
if (selectionContainsFalse)
{
generator.EmitGetValueFromNullableProperty(property, nullableBoolStorage);
generator.Emit(OpCodes.Brfalse, lblCheckNextProperty);
}
// If we've gotten this far without finding one of the values the user passed in, the record doesn't match, so return false.
generator.MarkLabel(lblReturnFalse);
generator.EmitReturnFalse();
generator.MarkLabel(lblCheckNextProperty);
}示例2: GenerateFilterIl
public override void GenerateFilterIl(ILGenerator generator, Dictionary<string, string> filterValues, PropertyInfo property)
{
Label lblReturnFalse = generator.DefineLabel();
Label lblNextProperty = generator.DefineLabel();
string minNumberString = filterValues["minNumber"];
string maxNumberString = filterValues["maxNumber"];
// If this is a nullable type such as bool?, the type is wrapped inside Nullable<> and we need to get the generic argument.
string myPropertyType = IsNullable ?
property.PropertyType.GetGenericArguments().Single().Name :
property.PropertyType.Name;
int storageIndex;
switch (myPropertyType)
{
// Regardless of the width of the integer coming in, we treat it as a 64-bit integer.
case "Byte":
case "Int16":
case "Int32":
case "Int64":
if (myPropertyType == "Byte") storageIndex = nullableByteStorage;
else if (myPropertyType == "Int16") storageIndex = nullableInt16Storage;
else if (myPropertyType == "Int32") storageIndex = nullableInt32Storage;
else storageIndex = nullableInt64Storage;
if (!string.IsNullOrWhiteSpace(minNumberString))
{
generator.EmitCheckHasValue(property, storageIndex);
generator.Emit(OpCodes.Brfalse, lblReturnFalse); // return false if the property is null
// the integer from the record.
generator.EmitGetValueFromNullableProperty(property, storageIndex);
generator.Emit(OpCodes.Conv_I8); // convert to 64-bit integer
// the minimum integer
generator.Emit(OpCodes.Ldc_I8, Convert.ToInt64(minNumberString));
// If the integer is less than the minimum, return false.
generator.Emit(OpCodes.Blt, lblReturnFalse);
}
if (!string.IsNullOrWhiteSpace(maxNumberString))
{
generator.EmitCheckHasValue(property, storageIndex);
generator.Emit(OpCodes.Brfalse, lblReturnFalse); // return false if the property is null
// the integer from the record.
generator.EmitGetValueFromNullableProperty(property, storageIndex);
generator.Emit(OpCodes.Conv_I8); // convert to 64-bit integer
// the maximum integer
generator.Emit(OpCodes.Ldc_I8, Convert.ToInt64(maxNumberString));
// If the integer is greater than the maximum, return false.
generator.Emit(OpCodes.Bgt, lblReturnFalse);
}
break;
// Floating point types
case "Single":
case "Double":
if (myPropertyType == "Single") storageIndex = nullableSingleStorage;
else storageIndex = nullableDoubleStorage;
if (!string.IsNullOrWhiteSpace(minNumberString))
{
generator.EmitCheckHasValue(property, storageIndex);
generator.Emit(OpCodes.Brfalse, lblReturnFalse); // return false if the integer is false
// the number from the record.
generator.EmitGetValueFromNullableProperty(property, storageIndex);
generator.Emit(OpCodes.Conv_R8); // convert to 64-bit floating-point number
// the minimum number
generator.Emit(OpCodes.Ldc_R8, Convert.ToDouble(minNumberString));
// If the number is less than the minimum, return false.
generator.Emit(OpCodes.Blt, lblReturnFalse);
}
if (!string.IsNullOrWhiteSpace(maxNumberString))
{
generator.EmitCheckHasValue(property, storageIndex);
generator.Emit(OpCodes.Brfalse, lblReturnFalse); // return false if the integer is false
// the number from the record.
generator.EmitGetValueFromNullableProperty(property, storageIndex);
generator.Emit(OpCodes.Conv_R8); // convert to 64-bit floating-point number
// the maximum number
generator.Emit(OpCodes.Ldc_R8, Convert.ToDouble(maxNumberString));
// If the number is greater than the maximum, return false.
generator.Emit(OpCodes.Bgt, lblReturnFalse);
}
break;
// TODO: DECIMAL type
}
generator.Emit(OpCodes.Br, lblNextProperty);
generator.MarkLabel(lblReturnFalse);
generator.EmitReturnFalse();
generator.MarkLabel(lblNextProperty);
}