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C#

Outlook -- Search Multiple Folders

See more Outlook Examples

I don't yet see how it's possible to do a recursive search of Outlook folders using the Microsoft Graph API. My best guess is to somehow use OData v4.0's $expand query option, but the hierarchical structure of the "mailFolder" and "messages" Microsoft Graph resources don't quite fit. Suggestions are welcome and can be sent to support@chilkatsoft.com.

This example will iterate over a list of folder previously obtained by a recursive traversal of the Outlook mail folders. (See the link in the example code below.)

A separate search is performed on each desired folder, and the results are combined into a single result set.

Note: This example requires Chilkat v9.5.0.68 or greater.

This example applies to: Exchange Online | Office 365 | Hotmail.com | Live.com | MSN.com | Outlook.com | Passport.com

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C#
bool success = false;

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

Chilkat.Http http = new Chilkat.Http();

//  Use your previously obtained access token here:
//  See the following examples for getting an access token:
//     Get Microsoft Graph OAuth2 Access Token (Azure AD v2.0 Endpoint).
//     Get Microsoft Graph OAuth2 Access Token (Azure AD Endpoint).
//     Refresh Access Token (Azure AD v2.0 Endpoint).
//     Refresh Access Token (Azure AD Endpoint).

http.AuthToken = "MICROSOFT_GRAPH_ACCESS_TOKEN";

//  This example will iterate over the folders previously discovered by recursively traversing the Outlook folders
//  as shown in this example:  Outlook Recursive Folder Traversal)

//  The XML map produced by the recursive traversal looks like this:

//  	<?xml version="1.0" encoding="utf-8"?>
//  	<hashtable>
//  	<e><k>/Sent Items</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAgEJAAAA</v></e>
//  	<e><k>/Inbox</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAgEMAAAA</v></e>
//  	<e><k>/Junk Email</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAgEiAAAA</v></e>
//  	<e><k>/Inbox/xyz</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwEAAAA=</v></e>
//  	<e><k>/Inbox/abc/subFolderA/a</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwIAAAA=</v></e>
//  	<e><k>/Inbox/abc</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huv8AAAA=</v></e>
//  	<e><k>/Outbox</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAgELAAAA</v></e>
//  	<e><k>/Inbox/abc/subFolderA</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwAAAQ==</v></e>
//  	<e><k>/Inbox/abc/subFolderB</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwMAAAA=</v></e>
//  	<e><k>/Archive</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAG8XunwAAAA=</v></e>
//  	<e><k>/Deleted Items</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAgEKAAAA</v></e>
//  	<e><k>/Drafts</k><v>AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAgEPAAAA</v></e>
//  	</hashtable>

//  We'll iterate over the folders, and search all folders beginning with "/Inbox" (effectively, we're recursively searching
//  everything under Inbox)
Chilkat.Xml xmlMap = new Chilkat.Xml();
success = xmlMap.LoadXmlFile("qa_data/outlook/folderMap.xml");
if (success != true) {
    Debug.WriteLine("Failed to load XML folder map.");
    return;
}

//  We're going to return just the message id, subject, and FROM name/address.
http.SetUrlVar("select","id,subject,from");

//  Our search will be for emails with the word "sample" in the subject.
http.SetUrlVar("filter","contains(subject,'sample')");

Chilkat.JsonObject json = new Chilkat.JsonObject();
json.EmitCompact = false;

Chilkat.JsonObject jsonCombined = new Chilkat.JsonObject();
jsonCombined.EmitCompact = false;

Chilkat.StringBuilder sbResponse = new Chilkat.StringBuilder();
Chilkat.StringBuilder sbPath = new Chilkat.StringBuilder();
int numFolders = xmlMap.NumChildren;
int i = 0;
int j = 0;
int k = 0;
while (i < numFolders) {
    xmlMap.I = i;
    sbPath.SetString(xmlMap.GetChildContent("e[i]|k"));

    if (sbPath.StartsWith("/Inbox",true) == true) {

        Debug.WriteLine("------------------------------------------------------------------");
        Debug.WriteLine("Searching " + sbPath.GetAsString());

        //  Search this mail folder..
        http.SetUrlVar("folder_id",xmlMap.GetChildContent("e[i]|v"));

        sbResponse.Clear();
        success = http.QuickGetSb("https://graph.microsoft.com/v1.0/me/mailFolders/{$folder_id}/messages?$filter={$filter}&$select={$select}",sbResponse);
        if ((success != true) && (http.LastStatus == 0)) {
            Debug.WriteLine(http.LastErrorText);
            return;
        }

        json.LoadSb(sbResponse);

        if (http.LastStatus != 200) {
            Debug.WriteLine("HTTP response status = " + Convert.ToString(http.LastStatus));
            Debug.WriteLine(json.Emit());
            Debug.WriteLine("Failed.");
            return;
        }

        Debug.WriteLine(json.Emit());

        //  Each mail folder search will return JSON with a value array, which is non-empty if any matching messages were found:

        //  			{
        //  			  "@odata.context": "https://graph.microsoft.com/v1.0/$metadata#users('me')/mailFolders('AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAgEMAAAA')/messages(id,subject,from)",
        //  			  "value": [
        //  				Individual messages, if any, are listed here.
        //  			  ]
        //  			}

        int numMessages = json.SizeOfArray("value");
        j = 0;
        while (j < numMessages) {
            json.J = j;

            //  Add this message to the final result set.
            jsonCombined.K = k;
            jsonCombined.UpdateString("value[k].folderPath",sbPath.GetAsString());
            jsonCombined.UpdateString("value[k].id",json.StringOf("value[j].id"));
            jsonCombined.UpdateString("value[k].subject",json.StringOf("value[j].subject"));
            jsonCombined.UpdateString("value[k].from.emailAddress.name",json.StringOf("value[j].from.emailAddress.name"));
            jsonCombined.UpdateString("value[k].from.emailAddress.address",json.StringOf("value[j].from.emailAddress.address"));
            k = k + 1;

            j = j + 1;
        }

    }

    i = i + 1;
}

//  Show the final combined JSON search result.
Debug.WriteLine("------------------------------------------------------------------");
Debug.WriteLine("Combined Search Results:");
Debug.WriteLine(jsonCombined.Emit());

//  Sample output for the above program:

//  ------------------------------------------------------------------
//  Searching /Inbox
//  {
//    "@odata.context": "https://graph.microsoft.com/v1.0/$metadata#users('me')/mailFolders('AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAgEMAAAA')/messages(id,subject,from)",
//    "value": [
//      {
//        "@odata.etag": "W/\"CQAAABYAAADn68XtMop0TpsYJGpfKXY9AADOpwfr\"",
//        "id": "AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgBGAAADsVyfxjDU406Ic4X7ill8xAcA5_vF7TKKdE6bGCRqXyl2PQAAAgEMAAAA5_vF7TKKdE6bGCRqXyl2PQAAAM6Jj10AAAA=",
//        "subject": "A sample email with Amazon in the body",
//        "from": {
//          "emailAddress": {
//            "name": "Chilkat Software",
//            "address": "support@chilkatsoft.com"
//          }
//        }
//      }
//    ]
//  }
//  
//  ------------------------------------------------------------------
//  Searching /Inbox/xyz
//  {
//    "@odata.context": "https://graph.microsoft.com/v1.0/$metadata#users('me')/mailFolders('AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwEAAAA%3D')/messages(id,subject,from)",
//    "value": [
//    ]
//  }
//  
//  ------------------------------------------------------------------
//  Searching /Inbox/abc/subFolderA/a
//  {
//    "@odata.context": "https://graph.microsoft.com/v1.0/$metadata#users('me')/mailFolders('AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwIAAAA%3D')/messages(id,subject,from)",
//    "value": [
//      {
//        "@odata.etag": "W/\"CQAAABYAAADn68XtMop0TpsYJGpfKXY9AADOpzfb\"",
//        "id": "AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgBGAAADsVyfxjDU406Ic4X7ill8xAcA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwIAAADn68XtMop0TpsYJGpfKXY9AAAAzombFQAAAA==",
//        "subject": "Sample email from admin@chilkat.io",
//        "from": {
//          "emailAddress": {
//            "name": "Chilkat Software",
//            "address": "admin@chilkat.io"
//          }
//        }
//      }
//    ]
//  }
//  
//  ------------------------------------------------------------------
//  Searching /Inbox/abc
//  {
//    "@odata.context": "https://graph.microsoft.com/v1.0/$metadata#users('me')/mailFolders('AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huv8AAAA%3D')/messages(id,subject,from)",
//    "value": [
//    ]
//  }
//  
//  ------------------------------------------------------------------
//  Searching /Inbox/abc/subFolderA
//  {
//    "@odata.context": "https://graph.microsoft.com/v1.0/$metadata#users('me')/mailFolders('AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwAAAQ%3D%3D')/messages(id,subject,from)",
//    "value": [
//    ]
//  }
//  
//  ------------------------------------------------------------------
//  Searching /Inbox/abc/subFolderB
//  {
//    "@odata.context": "https://graph.microsoft.com/v1.0/$metadata#users('me')/mailFolders('AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgAuAAADsVyfxjDU406Ic4X7ill8xAEA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwMAAAA%3D')/messages(id,subject,from)",
//    "value": [
//    ]
//  }
//  
//  ------------------------------------------------------------------
//  Combined Search Results:
//  {
//    "value": [
//      {
//        "folderPath": "/Inbox",
//        "id": "AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgBGAAADsVyfxjDU406Ic4X7ill8xAcA5_vF7TKKdE6bGCRqXyl2PQAAAgEMAAAA5_vF7TKKdE6bGCRqXyl2PQAAAM6Jj10AAAA=",
//        "subject": "A sample email with Amazon in the body",
//        "from": {
//          "emailAddress": {
//            "name": "Chilkat Software",
//            "address": "support@chilkatsoft.com"
//          }
//        }
//      },
//      {
//        "folderPath": "/Inbox/abc/subFolderA/a",
//        "id": "AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgBGAAADsVyfxjDU406Ic4X7ill8xAcA5_vF7TKKdE6bGCRqXyl2PQAAAL8huwIAAADn68XtMop0TpsYJGpfKXY9AAAAzombFQAAAA==",
//        "subject": "Sample email from admin@chilkat.io",
//        "from": {
//          "emailAddress": {
//            "name": "Chilkat Software",
//            "address": "admin@chilkat.io"
//          }
//        }
//      }
//    ]
//  }
//