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2026-06-10

图片转为base64字符串 - ImageToBase64 ​

函数简介 ​

将图片对象转换为Base64编码的字符串。

接口名称 ​

ImageToBase64

DLL调用 ​

long ImageToBase64(long ola, long image_ptr);

参数说明 ​

参数名类型说明
ola长整数型OLAPlug对象的指针，由 CreateCOLAPlugInterFace 接口生成。
image_ptr长整数型要转换的图片句柄

示例 ​

SDK 调用 ​

cpp
#include "OLAPlugServer.h"

OLAPlugServer ola;
std::string result = ola.ImageToBase64(0);
csharp
using OLAPlug;

var ola = new OLAPlugServer();
string result = ola.ImageToBase64(0);
python
from OLAPlugServer import OLAPlugServer

ola = OLAPlugServer()
result = ola.ImageToBase64(0)
java
import com.olaplug.OLAPlugServer;

OLAPlugServer ola = new OLAPlugServer();
String result = ola.ImageToBase64(0);
cpp
var ola = com("OlaPlug.OlaSoft")
var result = ola.ImageToBase64(0)
vbscript
Set ola = CreateObject("OlaPlug.OlaSoft")
result = ola.ImageToBase64(0)
text
.局部变量 ola, OLAPlug
ola.创建 ()
result ＝ ola.ImageToBase64(0)
aardio
import OLAPlugServer;
var ola = OLAPlugServer();
var result = ola.ImageToBase64(0);
text
变量 ola <类型 = OLAPlugServer>
ola = 新建 OLAPlugServer
文本型 result = ola.ImageToBase64(0)
cpp
#include "OLAPlugServer.h"

OLAPlugServer ola;
std::string result = ola.ImageToBase64(0);

原生 DLL 调用 ​

cpp
long instance = CreateCOLAPlugInterFace();
long ptr = ImageToBase64(instance, 0);
if (ptr != 0) {
    char buffer[512] = {0};
    GetStringFromPtr(ptr, buffer, sizeof(buffer));
    FreeStringPtr(ptr);
}
csharp
using System.Runtime.InteropServices;
using System.Text;

[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern long CreateCOLAPlugInterFace();
[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern int GetStringFromPtr(long ptr, StringBuilder lpString, int size);
[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern int FreeStringPtr(long ptr);
[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern int GetStringSize(long ptr);
[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern long ImageToBase64(long ola, long image_ptr);

long instance = CreateCOLAPlugInterFace();
long ptr = ImageToBase64(instance, 0);
if (ptr != 0) {
    StringBuilder sb = new StringBuilder(GetStringSize(ptr) + 1);
    GetStringFromPtr(ptr, sb, sb.Capacity);
    FreeStringPtr(ptr);
    string result = sb.ToString();
}
python
from ctypes import CDLL, c_int, c_int64, create_string_buffer

ola = CDLL("OLAPlug_x64.dll")
ola.CreateCOLAPlugInterFace.restype = c_int64
instance = ola.CreateCOLAPlugInterFace()
ptr = ola.ImageToBase64(instance, 0)
if ptr:
    buf = create_string_buffer(512)
    ola.GetStringFromPtr(ptr, buf, 512)
    ola.FreeStringPtr(ptr)
    result = buf.value.decode("utf-8")

返回值 ​

长整数型：成功返回Base64字符串指针，失败返回0。

注意事项 ​

  • 返回的字符串指针需调用 FreeStringPtr 释放内存。
  • Base64编码会使数据量增加约33%，大图片建议先压缩再转换。