XmlNodeGetChildren: Difference between revisions

Latest revision as of 20:29, 23 September 2016

This function returns all children of a particular XML node, or a particular child node.

Syntax

table/xmlnode xmlNodeGetChildren ( xmlnode parent, [ int index ] )

OOP Syntax Help! I don't understand this!

Method: xmlnode:getChildren(...)

Variable: .children

Required Arguments

parent: This is the xmlnode you want to retrieve one or all child nodes of.

Optional Arguments

index: If you only want to retrieve one particular child node, specify its (0-based) index here. For example if you only want the first node, specify 0; the fifth node has index 4, etc.

Returns

If index isn't specified, returns a table containing all child nodes. If index is specified, returns the corresponding child node if it exists. If no nodes are found, it returns an empty table. Returns false in case of failure.

Example

Click to collapse [-]

Server

Suppose you have an .xml file with random welcome messages:

<messages>
    <message>Welcome to the deathmatch server, enjoy your stay.</message>
    <message>Welcome. Be sure to get your free pizza at Matt's!</message>
    <message>Party going on at the LS beach, be there</message>
</messages>

To show a random message from this list to joining players, you could use the following code:

addEventHandler("onResourceStart", getResourceRootElement(),
    function()
        local xml = xmlLoadFile("welcome.xml")             -- open the XML file
        local messageNodes = xmlNodeGetChildren(xml)       -- get all child nodes of the root node (<messages>)
        g_WelcomeMessages = {}                             -- create a new global variable to store the welcome messages
        for i,node in ipairs(messageNodes) do              -- loop over all the message nodes
            g_WelcomeMessages[i] = xmlNodeGetValue(node)   -- retrieve the text in each node
        end
        xmlUnloadFile(xml)                                 -- close the XML file
    end
)

addEventHandler("onPlayerJoin", getRootElement(),
    function()
        local numMessages = #g_WelcomeMessages                        -- get the number of messages
        local message = g_WelcomeMessages[math.random(numMessages)]   -- pick a random message
        outputChatBox(message, source, 0, 255, 0)                     -- display it to the joining player
    end
)

@@ Line 1: / Line 1: @@
 __NOTOC__
 {{Server client function}}
-This function returns a single sub node or a list of sub nodes of a particular XML node.
+This function returns all children of a particular XML node, or a particular child node.
 ==Syntax==
-<syntaxhighlight lang="lua">xmlnode/table xmlNodeGetChildren( xmlnode parent, [ int index ])</syntaxhighlight>
+<syntaxhighlight lang="lua">table/xmlnode xmlNodeGetChildren ( xmlnode parent, [ int index ] )</syntaxhighlight>
+{{OOP||[[xmlnode]]:getChildren|children}}
 ===Required Arguments===
-* '''parent''': This is an [[xmlnode]] that you want to find the children under.
+* '''parent:''' This is the [[xmlnode]] you want to retrieve one or all child nodes of.
 ===Optional Arguments===
-{{OptionalArg}}
+* '''index:''' If you only want to retrieve one particular child node, specify its (0-based) index here. For example if you only want the first node, specify 0; the fifth node has index 4, etc.
-* '''index''': This is the index of the node you wish to find. For example, to find the 5th subnode, you would use 4 as the index value. To find the first occurence, use 0. If this is not set, it will return a list of all children.
 ===Returns===
-If index isn't specified, it returns a list of all children. Returns an [[xmlnode]] object if index was set and a node was found, otherwise it returns false.
+If '''index''' isn't specified, returns a table containing all child nodes. If '''index''' is specified, returns the corresponding child node if it exists. If no nodes are found, it returns an empty table. Returns ''false'' in case of failure.
 ==Example==
 <section name="Server" class="server" show="true">
-If you wanted to find the 'instructions' node in a map file like this:
+Suppose you have an .xml file with random welcome messages:
 <syntaxhighlight lang="xml">
-<map version="2.0">
+<messages>
-      <options>
+    <message>Welcome to the deathmatch server, enjoy your stay.</message>
-            <instructions>Start at the begining and keep going until the end!</instructions>
+    <message>Welcome. Be sure to get your free pizza at Matt's!</message>
-      </options>
+    <message>Party going on at the LS beach, be there</message>
-</map>
+</messages>
 </syntaxhighlight>
-You could use the following code:
+To show a random message from this list to joining players, you could use the following code:
 <syntaxhighlight lang="lua">
-maproot = getLoadedMapXMLRoot ();
+addEventHandler("onResourceStart", getResourceRootElement(),
-optionsnode = xmlNodeGetChildren( maproot, 0 ); -- In this case it would find the options sub node as the first under the 'map' node
+    function()
+        local xml = xmlLoadFile("welcome.xml")             -- open the XML file
+        local messageNodes = xmlNodeGetChildren(xml)       -- get all child nodes of the root node (<messages>)
+        g_WelcomeMessages = {}                             -- create a new global variable to store the welcome messages
+        for i,node in ipairs(messageNodes) do              -- loop over all the message nodes
+            g_WelcomeMessages[i] = xmlNodeGetValue(node)   -- retrieve the text in each node
+        end
+        xmlUnloadFile(xml)                                 -- close the XML file
+    end
+)
+addEventHandler("onPlayerJoin", getRootElement(),
+    function()
+        local numMessages = #g_WelcomeMessages                        -- get the number of messages
+        local message = g_WelcomeMessages[math.random(numMessages)]   -- pick a random message
+        outputChatBox(message, source, 0, 255, 0)                     -- display it to the joining player
+    end
+)
 </syntaxhighlight>
 </section>
 ==See Also==
 {{XML functions}}
+[[ru:xmlNodeGetChildren]]