/// <exception cref="NotSupportedException" />
/// <exception cref="InvalidOperationException" />
private IEnumerable <T> FilterStringStartsWith(MethodCallExpression methodCall)
{
if (methodCall.Method.DeclaringType == typeof(String) &&
methodCall.Method.Name == nameof(String.StartsWith))
{
IComparsionIndex <T> index = FindComparsionIndex(methodCall.Object);
string keyFrom = (string)methodCall.Arguments.First().GetValue();
if (String.IsNullOrEmpty(keyFrom))
{
return(index.GreaterThan(keyFrom, false));
}
char lastChar = keyFrom[keyFrom.Length - 1];
string keyTo = keyFrom.Substring(0, keyFrom.Length - 1) + (char)(lastChar + 1);
return(index.Between(keyFrom, false, keyTo, true));
}
throw new NotSupportedException(
$"Predicate body {methodCall} should be String.StartsWith()");
}
