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Unicode C++

Find a Label ID by Name

See more GMail REST API Examples

Lookup the ID of a GMail label by the label name.

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkHttpW.h>
#include <CkStringBuilderW.h>
#include <CkJsonObjectW.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkHttpW http;
    http.put_AuthToken(L"GMAIL-ACCESS-TOKEN");

    const wchar_t *userId = L"me";
    http.SetUrlVar(L"userId",userId);

    const wchar_t *url = L"https://www.googleapis.com/gmail/v1/users/{$userId}/labels";

    //  Get the list of GMail labels as JSON.
    CkStringBuilderW sb;
    success = http.QuickGetSb(url,sb);
    if (success != true) {
        wprintf(L"%s\n",http.lastErrorText());
        return;
    }

    CkJsonObjectW json;
    json.LoadSb(sb);
    json.put_EmitCompact(false);
    wprintf(L"%s\n",json.emit());

    if (http.get_LastStatus() != 200) {
        wprintf(L"Failed.\n");
        return;
    }

    //  The JSON returned looks like this:
    //  {
    //    "labels": [
    //      {
    //        "id": "Label_5",
    //        "name": "QA",
    //        "messageListVisibility": "show",
    //        "labelListVisibility": "labelShow",
    //        "type": "user"
    //      },
    //      {
    //        "id": "Label_21",
    //        "name": "[Gmail]/testFolder",
    //        "type": "user"
    //      },
    //      {
    //        "id": "CATEGORY_PERSONAL",
    //        "name": "CATEGORY_PERSONAL",
    //        "type": "system"
    //      },
    //  	...

    //  The name of the label is generally known because it's what we visually see.
    //  The id is what we need to get.  Assuming the name is unique,
    //  find the JSON record having name=<desired name>
    //  For example...
    CkJsonObjectW *jRecord = json.FindRecord(L"labels",L"name",L"QA",false);
    if (json.get_LastMethodSuccess() == true) {
        wprintf(L"The id of QA is: %s\n",jRecord->stringOf(L"id"));
        delete jRecord;
    }

    jRecord = json.FindRecord(L"labels",L"name",L"[Gmail]/testFolder",false);
    if (json.get_LastMethodSuccess() == true) {
        wprintf(L"The id of [Gmail]/testFolder is: %s\n",jRecord->stringOf(L"id"));
        delete jRecord;
    }

    jRecord = json.FindRecord(L"labels",L"name",L"questions",false);
    if (json.get_LastMethodSuccess() == true) {
        wprintf(L"The id of questions is: %s\n",jRecord->stringOf(L"id"));
        delete jRecord;
    }

    //  Output:

    //  The id of QA is: Label_5
    //  The id of [Gmail]/testFolder is: Label_21
    //  The id of questions is: Label_43
    }