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C

Get a List of Message IDs in GMail User's Mailbox

See more GMail REST API Examples

Demonstrates how to get a list of message IDs in a GMail mailbox. The "userId" can be either the user's email address or the special value "me" to indicate the authenticated user.

Chilkat C Downloads

C
#include <C_CkHttp.h>
#include <C_CkHttpResponse.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkHttp http;
    HCkHttpResponse resp;
    HCkJsonObject jsonResponse;
    const char *id;
    const char *threadId;
    int resultSizeEstimate;
    int i;
    int count_i;

    success = FALSE;

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

    http = CkHttp_Create();

    CkHttp_putAuthToken(http,"ACCESS_TOKEN");

    CkHttp_putAccept(http,"application/json");

    resp = CkHttpResponse_Create();
    success = CkHttp_HttpNoBody(http,"GET","https://www.googleapis.com/gmail/v1/users/userId/messages",resp);
    if (success == FALSE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkHttp_Dispose(http);
        CkHttpResponse_Dispose(resp);
        return;
    }

    printf("Response Status Code: %d\n",CkHttpResponse_getStatusCode(resp));

    jsonResponse = CkJsonObject_Create();
    CkJsonObject_Load(jsonResponse,CkHttpResponse_bodyStr(resp));
    CkJsonObject_putEmitCompact(jsonResponse,FALSE);
    printf("%s\n",CkJsonObject_emit(jsonResponse));

    if (CkHttpResponse_getStatusCode(resp) != 200) {
        printf("Failed.\n");
        CkHttp_Dispose(http);
        CkHttpResponse_Dispose(resp);
        CkJsonObject_Dispose(jsonResponse);
        return;
    }

    // {
    //   "messages": [
    //     users.messages Resource
    //   ],
    //   "nextPageToken": string,
    //   "resultSizeEstimate": unsigned integer
    // }

    // Chilkat functions returning "const char *" return a pointer to temporary internal memory owned and managed by Chilkat.
    // See this example explaining how this memory should be used: const char * functions.

    resultSizeEstimate = CkJsonObject_IntOf(jsonResponse,"resultSizeEstimate");
    i = 0;
    count_i = CkJsonObject_SizeOfArray(jsonResponse,"messages");
    while (i < count_i) {
        CkJsonObject_putI(jsonResponse,i);
        id = CkJsonObject_stringOf(jsonResponse,"messages[i].id");
        threadId = CkJsonObject_stringOf(jsonResponse,"messages[i].threadId");
        i = i + 1;
    }



    CkHttp_Dispose(http);
    CkHttpResponse_Dispose(resp);
    CkJsonObject_Dispose(jsonResponse);

    }