/// <summary> Append a key. The key will be associated with the next value. In an
/// object, every value must be preceded by a key.
/// </summary>
/// <param name="s">A key string.
/// </param>
/// <returns> this
/// </returns>
/// <throws> JSONException If the key is out of place. For example, keys </throws>
/// <summary> do not belong in arrays or if the key is null.
/// </summary>
public virtual JSONWriter key(System.String s)
{
if (s == null)
{
throw new JSONException("Null key.");
}
if (this.mode == 'k')
{
try
{
stack[top - 1].putOnce(s, (System.Object)true);
if (this.comma)
{
this.writer.Write(',');
}
this.writer.Write(JSONObject.quote(s));
this.writer.Write(':');
this.comma = false;
this.mode = 'o';
return(this);
}
catch (System.IO.IOException e)
{
throw new JSONException(e);
}
}
throw new JSONException("Misplaced key.");
}