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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 <C_CkHttpW.h>
#include <C_CkStringBuilderW.h>
#include <C_CkJsonObjectW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkHttpW http;
    const wchar_t *userId;
    const wchar_t *url;
    HCkStringBuilderW sb;
    HCkJsonObjectW json;
    HCkJsonObjectW jRecord;

    success = FALSE;

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

    http = CkHttpW_Create();
    CkHttpW_putAuthToken(http,L"GMAIL-ACCESS-TOKEN");

    userId = L"me";
    CkHttpW_SetUrlVar(http,L"userId",userId);

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

    // Get the list of GMail labels as JSON.
    sb = CkStringBuilderW_Create();
    success = CkHttpW_QuickGetSb(http,url,sb);
    if (success != TRUE) {
        wprintf(L"%s\n",CkHttpW_lastErrorText(http));
        CkHttpW_Dispose(http);
        CkStringBuilderW_Dispose(sb);
        return;
    }

    json = CkJsonObjectW_Create();
    CkJsonObjectW_LoadSb(json,sb);
    CkJsonObjectW_putEmitCompact(json,FALSE);
    wprintf(L"%s\n",CkJsonObjectW_emit(json));

    if (CkHttpW_getLastStatus(http) != 200) {
        wprintf(L"Failed.\n");
        CkHttpW_Dispose(http);
        CkStringBuilderW_Dispose(sb);
        CkJsonObjectW_Dispose(json);
        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...
    jRecord = CkJsonObjectW_FindRecord(json,L"labels",L"name",L"QA",FALSE);
    if (CkJsonObjectW_getLastMethodSuccess(json) == TRUE) {
        wprintf(L"The id of QA is: %s\n",CkJsonObjectW_stringOf(jRecord,L"id"));
        CkJsonObjectW_Dispose(jRecord);
    }

    jRecord = CkJsonObjectW_FindRecord(json,L"labels",L"name",L"[Gmail]/testFolder",FALSE);
    if (CkJsonObjectW_getLastMethodSuccess(json) == TRUE) {
        wprintf(L"The id of [Gmail]/testFolder is: %s\n",CkJsonObjectW_stringOf(jRecord,L"id"));
        CkJsonObjectW_Dispose(jRecord);
    }

    jRecord = CkJsonObjectW_FindRecord(json,L"labels",L"name",L"questions",FALSE);
    if (CkJsonObjectW_getLastMethodSuccess(json) == TRUE) {
        wprintf(L"The id of questions is: %s\n",CkJsonObjectW_stringOf(jRecord,L"id"));
        CkJsonObjectW_Dispose(jRecord);
    }

    // Output:

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


    CkHttpW_Dispose(http);
    CkStringBuilderW_Dispose(sb);
    CkJsonObjectW_Dispose(json);

    }