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How to: Return List Items

Applies to: SharePoint Foundation 2010

This programming task shows how to create a Windows form that uses the GetListItems method of the Lists Web service to return items from a list.

Procedures

Before you begin, create a Windows Forms application in Microsoft Visual Studio. For information about setting a Web reference to a SharePoint Foundation Web service, see Web Service Guidelines.

To add code to display the collection of list items

  1. After creating a Windows Forms application and adding a Web reference, open Form1 in Design view, open the Toolbox, and then drag a Label control and a Button control onto the form.

  2. Right-click the Label control, click Properties, and then delete the value "Label1" from the Text property of the control.

  3. Double-click the button to display the Code Editor, and add the following lines of code to the Button1_Click event handler.

    'Declare and initialize a variable for the Lists Web service.
    Dim listService As New Web_Reference.Lists()
    
    'Authenticate the current user by passing their default 
    'credentials to the Web service from the system credential cache.
    listService.Credentials = System.Net.CredentialCache.DefaultCredentials
    
    'Set the Url property of the service for the path to a subsite.
    listService.Url = "http://Server_Name/Subsite_Name/_vti_bin/Lists.asmx"
    
    'Instantiate an XmlDocument object.
    Dim xmlDoc As New System.Xml.XmlDocument()
    
    'Assign values to the string parameters of the GetListItems method, 
    'using GUIDs for the listName and viewName variables. For listName, 
    'using the list display name will also work, but using the list GUID 
    'is recommended. For viewName, only the view GUID can be used. 
    'Using an empty string for viewName causes the default view 
    'to be used.
    Dim listName As String = "{17991794-81BB-494F-9910-CFBF1093A7CF}"
    Dim viewName As String = "{7137FFF8-48FF-4C69-8C76-0E3BBD1EA7F9}"
    Dim rowLimit As String = "150"
    
    'Use the CreateElement method of the document object to create 
    'elements for the parameters that use XML.
    Dim query As System.Xml.XmlElement = xmlDoc.CreateElement("Query")
    Dim viewFields As System.Xml.XmlElement = xmlDoc.CreateElement("ViewFields")
    Dim queryOptions As System.Xml.XmlElement = xmlDoc.CreateElement("QueryOptions")
    
    'To specify values for the parameter elements (optional), assign CAML 
    ' fragments to the InnerXml property of each element.
    query.InnerXml = "<Where><Gt><FieldRef Name=""ID"" />" + 
    "<Value Type=""Counter"">3</Value></Gt></Where>"
    viewFields.InnerXml = "<FieldRef Name=""Title"" />"
    queryOptions.InnerXml = ""
    
    'Declare an XmlNode object and initialize it with the XML response 
    'from the GetListItems method. The last parameter specifies 
    'the GUID of the Web site containing the list. Setting it to 
    'Nothing causes the Web site specified by the Url property 
    'to be used.
    Dim nodeListItems As System.Xml.XmlNode = listService.GetListItems(listName, viewName, query, viewFields, rowLimit, queryOptions, Nothing)
    
    'Loop through each node in the XML response and display each item.
    Dim listItem As System.Xml.XmlNode
    For Each listItem In  nodeListItems
       label1.Text += listItem.OuterXml
    Next listItem
    
    /*Declare and initialize a variable for the Lists Web service.*/
    Web_Reference.Lists listService = new Web_Reference.Lists();
    
    /*Authenticate the current user by passing their default 
    credentials to the Web service from the system credential cache.*/
    listService.Credentials = 
        System.Net.CredentialCache.DefaultCredentials;
    
    /*Set the Url property of the service for the path to a subsite.*/
    listService.Url = 
        "http://Server_Name/Subsite_Name/_vti_bin/Lists.asmx";
    
    /* Instantiate an XmlDocument object */
    System.Xml.XmlDocument xmlDoc = new System.Xml.XmlDocument();
    
    /* Assign values to the string parameters of the GetListItems method, 
    using GUIDs for the listName and viewName variables. For listName, 
    using the list display name will also work, but using the list GUID 
    is recommended. For viewName, only the view GUID can be used. 
    Using an empty string for viewName causes the default view to be used.*/
    string listName = "{17991794-81BB-494F-9910-CFBF1093A7CF}";
    string viewName = "{7137FFF8-48FF-4C69-8C76-0E3BBD1EA7F9}";
    string rowLimit = "150";
    
    /*Use the CreateElement method of the document object to create 
    elements for the parameters that use XML.*/
    System.Xml.XmlElement query = xmlDoc.CreateElement("Query");
    System.Xml.XmlElement viewFields = 
        xmlDoc.CreateElement("ViewFields");
    System.Xml.XmlElement queryOptions = 
        xmlDoc.CreateElement("QueryOptions");
    
    /*To specify values for the parameter elements (optional), assign 
    CAML fragments to the InnerXml property of each element.*/
    query.InnerXml = "<Where><Gt><FieldRef Name=\"ID\" />" +
        "<Value Type=\"Counter\">3</Value></Gt></Where>";
    viewFields.InnerXml = "<FieldRef Name=\"Title\" />";
    queryOptions.InnerXml = "";
    
    /* Declare an XmlNode object and initialize it with the XML response 
    from the GetListItems method. The last parameter specifies the GUID 
    of the Web site containing the list. Setting it to null causes the 
    Web site specified by the Url property to be used.*/
    System.Xml.XmlNode nodeListItems = 
        listService.GetListItems
        (listName, viewName,query,viewFields,rowLimit,queryOptions,null);
    
    /*Loop through each node in the XML response and display each item.*/
    foreach (System.Xml.XmlNode listItem in nodeListItems)
    {
        label1.Text += listItem.OuterXml;
    }
    

    Note

    You must provide your own values for the listName, viewName, and rowLimit variables that are used in the example.

  4. On the Debug menu, click Start Debugging to test the form. Click the button in the form to display the list items from the specified list.