public static ModelMetadata FromStringExpression(string expression, TemplateData templateData, IModelMetadataProvider provider)
{
if (string.IsNullOrWhiteSpace(expression))
{
return(templateData.ModelMetadata);
}
var templateDataInfo = TemplateDataEvaluator.Eval(templateData, expression);
Type containerType = null;
Type modelType = null;
Func <object> modelAccessor = null;
string propertyName = null;
bool valid = (templateDataInfo != null);
if (templateDataInfo != null)
{
if (templateDataInfo.Container != null)
{
containerType = templateDataInfo.Container.GetType();
}
modelAccessor = () => templateDataInfo.Value;
if (templateDataInfo.PropertyInfo != null)
{
propertyName = templateDataInfo.PropertyInfo.Name;
modelType = templateDataInfo.PropertyInfo.PropertyType;
}
else if (templateDataInfo.Value != null)
{
modelType = templateDataInfo.Value.GetType();
}
}
else if (templateData.ModelMetadata != null)
{
var propertyMetadata = templateData.ModelMetadata.Properties.FirstOrDefault(p => p.PropertyName == expression);
if (propertyMetadata != null)
{
return(propertyMetadata);
}
}
var metadata = GetMetadataFromProvider(modelAccessor, modelType ?? typeof(string), propertyName, containerType, provider);
if (!valid)
{
metadata.Valid = false;
}
return(metadata);
}
public static ModelMetadata FromStringExpression(string expression, TemplateData templateData, IModelMetadataProvider provider)
{
if (string.IsNullOrWhiteSpace(expression))
{
return templateData.ModelMetadata;
}
var templateDataInfo = TemplateDataEvaluator.Eval(templateData, expression);
Type containerType = null;
Type modelType = null;
Func<object> modelAccessor = null;
string propertyName = null;
if (templateDataInfo != null)
{
if (templateDataInfo.Container != null)
{
containerType = templateDataInfo.Container.GetType();
}
modelAccessor = () => templateDataInfo.Value;
if (templateDataInfo.PropertyInfo != null)
{
propertyName = templateDataInfo.PropertyInfo.Name;
modelType = templateDataInfo.PropertyInfo.PropertyType;
}
else if (templateDataInfo.Value != null)
{
modelType = templateDataInfo.Value.GetType();
}
}
else if (templateData.ModelMetadata != null)
{
var propertyMetadata = templateData.ModelMetadata.Properties.FirstOrDefault(p => p.PropertyName == expression);
if (propertyMetadata != null)
{
return propertyMetadata;
}
}
return GetMetadataFromProvider(modelAccessor, modelType ?? typeof(string), propertyName, containerType, provider);
}
public static TemplateDataInfo Eval(TemplateData templateData, string expression)
{
return(EvalComplexExpression(templateData, expression));
}
public static TemplateDataInfo Eval(TemplateData templateData, string expression)
{
return EvalComplexExpression(templateData, expression);
}
/// <summary>
/// Resolves the value for the given expression.
/// </summary>
/// <param name="context">The render context.</param>
/// <param name="templateData">The template data.</param>
/// <param name="expression">The expression.</param>
/// <param name="isVariableLookup">True if this is a variable lookup, otherwise false.</param>
/// <returns>The resolved value.</returns>
public static object ResolveValue(RenderContext context, TemplateData templateData, string expression, bool isVariableLookup)
{
if (isVariableLookup && !string.IsNullOrEmpty(expression) && !expression.StartsWith("root."))
{
return context.GetVariable(expression);
}
if (isVariableLookup && !string.IsNullOrEmpty(expression) && expression.StartsWith("root."))
{
context = context.RootRenderContext ?? context;
templateData = context.TemplateData;
expression = expression.Substring(5);
}
var modelMetadata = ExpressionMetadataProvider.FromStringExpression(expression, templateData, context.ModelMetadataProvider);
if (modelMetadata == null)
{
return null;
}
return modelMetadata.Model;
}