/// <summary>
/// Initializes a new instance of the <see cref="DataBindingSetterBuilder"/> class.
/// </summary>
/// <param name="expressionType">The type of the bound expression.</param>
/// <param name="dataSourceType">The type of the data source to which the value is being bound.</param>
/// <param name="expression">The binding expression with which to bind the dependency property.</param>
public DataBindingSetterBuilder(Type expressionType, Type dataSourceType, String expression)
: base(dataSourceType)
{
this.boundType = expressionType;
this.delegateType = typeof(DataBindingSetter <>).MakeGenericType(expressionType);
if (UltravioletPlatformInfo.IsRuntimeCodeGenerationSupported())
{
CreateReturnTarget();
var path = BindingExpressions.GetBindingMemberPathPart(expression);
var pathParts = path.Contains(".") ? path.Split('.') : null;
var pathFinalPart = (pathParts == null) ? path : pathParts[pathParts.Length - 1];
var current = AddDataSourceReference();
var value = AddValueParameter();
if (current.Type.IsValueType)
{
return;
}
if (pathParts != null)
{
for (int i = 0; i < pathParts.Length - 1; i++)
{
current = AddSafeReference(expression, current, pathParts[i]);
}
}
if (!AddValueAssignment(current, value, pathFinalPart))
{
return;
}
AddReturn();
AddReturnLabel();
var lambdaBody = Expression.Block(variables, expressions);
var lambda = Expression.Lambda(delegateType, lambdaBody, parameters);
lambdaExpression = lambda;
}
else
{
var expParamDataSource = Expression.Parameter(typeof(Object), "dataSource");
var expParamValue = Expression.Parameter(boundType, "value");
var implMethod = typeof(DataBindingSetterBuilder).GetMethod(nameof(ReflectionBasedImplementation),
BindingFlags.NonPublic | BindingFlags.Static);
var path = BindingExpressions.GetBindingMemberPathPart(expression);
var pathParts = path.Contains(".") ? path.Split('.') : null;
var pathFinalPart = (pathParts == null) ? path : pathParts[pathParts.Length - 1];
var expDataSource = (Expression)Expression.Convert(expParamDataSource, dataSourceType);
var expDataSourceType = dataSourceType;
var current = dataSourceType;
if (pathParts != null)
{
for (int i = 0; i < pathParts.Length - 1; i++)
{
expDataSourceType = BindingExpressions.GetMemberType(BindingExpressions.FindPropertyOrField(expDataSourceType, pathParts[i]));
expDataSource = Expression.PropertyOrField(expDataSource, pathParts[i]);
}
}
var member = BindingExpressions.FindPropertyOrField(expDataSourceType, pathFinalPart);
if (!BindingExpressions.CanWriteMember(member))
{
return;
}
var expImplMethodCall = Expression.Call(implMethod,
Expression.Constant(member),
Expression.Convert(expDataSource, typeof(Object)),
Expression.Convert(expParamValue, typeof(Object)));
lambdaExpression = Expression.Lambda(delegateType, expImplMethodCall, expParamDataSource, expParamValue);
}
}
