/// <summary>
/// Replaces existing query parameter(s) or appends to the end. If value is a collection type (array, IEnumerable, etc.),
/// multiple parameters are added, i.e. x=1&x=2. If any of the same name already exist, they are overwritten one by one
/// (preserving order) and any remaining are appended to the end. If fewer values are specified than already exist,
/// remaining existing values are removed.
/// </summary>
/// <param name="name">Name of the parameter.</param>
/// <param name="value">Value of the parameter. If it's a collection, multiple parameters of the same name are added/replaced.</param>
/// <param name="isEncoded">If true, assume value(s) already URL-encoded.</param>
/// <param name="nullValueHandling">Describes how to handle null values.</param>
public void AddOrReplace(string name, object value, bool isEncoded = false, NullValueHandling nullValueHandling = NullValueHandling.Remove)
{
if (!Contains(name))
{
Add(name, value, isEncoded, nullValueHandling);
}
// This covers some complex edge cases involving multiple values of the same name.
// example: x has values at positions 2 and 4 in the query string, then we set x to
// an array of 4 values. We want to replace the values at positions 2 and 4 with the
// first 2 values of the new array, then append the remaining 2 values to the end.
//var parameters = this.Where(p => p.Name == name).ToArray();
var values = new Queue <object>(SplitCollection(value));
var old = _values.ToArray();
_values.Clear();
foreach (var item in old)
{
if (item.Name != name)
{
_values.Add(item);
continue;
}
if (!values.Any())
{
continue; // remove, effectively
}
var val = values.Dequeue();
if (val == null && nullValueHandling == NullValueHandling.Ignore)
{
_values.Add(item);
}
else if (val == null && nullValueHandling == NullValueHandling.Remove)
{
continue;
}
else
{
Add(name, val, isEncoded, nullValueHandling);
}
}
// add the rest to the end
while (values.Any())
{
Add(name, values.Dequeue(), isEncoded, nullValueHandling);
}
}