/// <summary>
/// Selects a <see cref="JsonElement"/> using a JSONPath expression. Selects the token that matches the object path.
/// </summary>
/// <param name="path">
/// A <see cref="String"/> that contains a JSONPath expression.
/// </param>
/// <param name="errorWhenNoMatch">A flag to indicate whether an error should be thrown if no tokens are found when evaluating part of the expression.</param>
/// <returns>A <see cref="JsonDocument"/>.</returns>
public static JsonElement?SelectElement(this JsonDocument src, string path, bool errorWhenNoMatch)
{
var p = new JsonDocumentPath(path);
JsonElement?el = null;
foreach (JsonElement t in p.Evaluate(src.RootElement, src.RootElement, errorWhenNoMatch))
{
if (el != null)
{
throw new JsonException("Path returned multiple tokens.");
}
el = t;
}
return(el);
}
private IEnumerable <JsonElement?> GetResult(JsonElement root, JsonElement t, object?o)
{
if (o is JsonElement resultToken)
{
return(new JsonElement?[1] {
resultToken
});
}
if (o is List <PathFilter> pathFilters)
{
return(JsonDocumentPath.Evaluate(pathFilters, root, t, false));
}
return(Enumerable.Empty <JsonElement?>());
}
/// <summary>
/// Selects a collection of elements using a JSONPath expression.
/// </summary>
/// <param name="path">
/// A <see cref="String"/> that contains a JSONPath expression.
/// </param>
/// <param name="errorWhenNoMatch">A flag to indicate whether an error should be thrown if no tokens are found when evaluating part of the expression.</param>
/// <returns>An <see cref="IEnumerable{T}"/> of <see cref="JsonDocument"/> that contains the selected elements.</returns>
public static IEnumerable <JsonElement?> SelectElements(this JsonDocument src, string path, bool errorWhenNoMatch)
{
var parser = new JsonDocumentPath(path);
return(parser.Evaluate(src.RootElement, src.RootElement, errorWhenNoMatch));
}
