protected virtual Delegate GetMethodDelegateInternal(Type delegateType, MethodInfo method)
{
lock (InvokeMethodCacheDelegate)
{
var cacheKey = new MethodDelegateCacheKey(method, delegateType);
Delegate value;
if (!InvokeMethodCacheDelegate.TryGetValue(cacheKey, out value))
{
GenerateInvokeMethodCode(method, delegateType);
MethodInfo delegateMethod = delegateType.GetMethodEx(nameof(Action.Invoke));
if (delegateMethod == null)
{
throw new ArgumentException(string.Empty, nameof(delegateType));
}
var delegateParams = delegateMethod.GetParameters().ToList();
ParameterInfo[] methodParams = method.GetParameters();
var expressions = new List <Expression>();
var parameters = new List <ParameterExpression>();
if (!method.IsStatic)
{
var thisParam = Expression.Parameter(delegateParams[0].ParameterType, "@this");
parameters.Add(thisParam);
expressions.Add(ConvertIfNeed(thisParam, method.DeclaringType, false));
delegateParams.RemoveAt(0);
}
Should.BeValid("delegateType", delegateParams.Count == methodParams.Length);
for (int i = 0; i < methodParams.Length; i++)
{
ParameterExpression parameter = Expression.Parameter(delegateParams[i].ParameterType, i.ToString());
parameters.Add(parameter);
expressions.Add(ConvertIfNeed(parameter, methodParams[i].ParameterType, false));
}
Expression callExpression;
if (method.IsStatic)
{
callExpression = Expression.Call(null, method, expressions.ToArrayEx());
}
else
{
Expression @this = expressions[0];
expressions.RemoveAt(0);
callExpression = Expression.Call(@this, method, expressions.ToArrayEx());
}
if (delegateMethod.ReturnType != typeof(void))
{
callExpression = ConvertIfNeed(callExpression, delegateMethod.ReturnType, false);
}
var lambdaExpression = Expression.Lambda(delegateType, callExpression, parameters);
value = lambdaExpression.Compile();
InvokeMethodCacheDelegate[cacheKey] = value;
}
return(value);
}
}
/// <summary>
/// Gets a delegate to call the specified <see cref="MethodInfo" />.
/// </summary>
/// <param name="delegateType">The type of delegate.</param>
/// <param name="method">
/// The specified <see cref="MethodInfo" />
/// </param>
/// <returns>
/// An instance of delegate.
/// </returns>
public virtual Delegate GetMethodDelegate(Type delegateType, MethodInfo method)
{
Should.NotBeNull(delegateType, "delegateType");
Should.BeOfType <Delegate>(delegateType, "delegateType");
Should.NotBeNull(method, "method");
lock (InvokeMethodCacheDelegate)
{
var cacheKey = new MethodDelegateCacheKey(method, delegateType);
Delegate value;
if (!InvokeMethodCacheDelegate.TryGetValue(cacheKey, out value))
{
MethodInfo delegateMethod = delegateType.GetMethodEx("Invoke");
var delegateParams = delegateMethod.GetParameters().ToList();
ParameterInfo[] methodParams = method.GetParameters();
var expressions = new List <Expression>();
var parameters = new List <ParameterExpression>();
if (!method.IsStatic)
{
var thisParam = Expression.Parameter(delegateParams[0].ParameterType, "@this");
parameters.Add(thisParam);
expressions.Add(ConvertIfNeed(thisParam, GetDeclaringType(method), false));
delegateParams.RemoveAt(0);
}
Should.BeValid("delegateType", delegateParams.Count == methodParams.Length);
for (int i = 0; i < methodParams.Length; i++)
{
ParameterExpression parameter = Expression.Parameter(delegateParams[i].ParameterType, i.ToString());
parameters.Add(parameter);
expressions.Add(ConvertIfNeed(parameter, methodParams[i].ParameterType, false));
}
Expression callExpression;
if (method.IsStatic)
{
callExpression = Expression.Call(null, method, expressions.ToArrayEx());
}
else
{
Expression @this = expressions[0];
expressions.RemoveAt(0);
callExpression = Expression.Call(@this, method, expressions.ToArrayEx());
}
if (delegateMethod.ReturnType != typeof(void))
{
callExpression = ConvertIfNeed(callExpression, delegateMethod.ReturnType, false);
}
var lambdaExpression = CreateLambdaExpressionByType(delegateType, callExpression, parameters);
value = lambdaExpression.Compile();
InvokeMethodCacheDelegate[cacheKey] = value;
}
return(value);
}
}
