先前介紹讀取檔案 (Read File)，是以一行一行逐步讀取，現在我們想要一次讀取整個檔案為字串，再來做其它處理，這樣可以怎麼實作呢？
這個檔案內容是關於人臉資訊的JSON檔，包含年齡、性別、姿勢、種族、微笑等等量化資訊。
想要讀取整個檔案為字串就靠內建函式，幾行程式碼就能實現！
將檔案放置到專案可以讀取到的位址，在程式碼中設定該檔名：
/**
Theme: Read Whole File to String
IDE: Xcode 7
Language: C++
Date: 105/04/04
Author: HappyMan
Blog: https://cg2010studio.wordpress.com/
*/
#include <iostream>
#include <fstream>
using namespace cv;
using namespace std;
int main(int argc, char** argv)
{
ifstream inFile;
inFile.open("HappyFace.json");// Open the input file
stringstream strStream;
strStream << inFile.rdbuf();// Read the file
string string = strStream.str();// string holds the content of the file
cout << string << endl;// You can do anything with the string
return 0;
}
編譯執行後列印：
{
"face": [
{
"attribute": {
"age": {
"range": 5,
"value": 29
},
"gender": {
"confidence": 99.9984,
"value": "Female"
},
"glass": {
"confidence": 99.9052,
"value": "None"
},
"pose": {
"pitch_angle": {
"value": 0.000004
},
"roll_angle": {
"value": -6.40648
},
"yaw_angle": {
"value": -0.188313
}
},
"race": {
"confidence": 99.1486,
"value": "Asian"
},
"smiling": {
"value": 96.3368
}
},
"face_id": "8afb059d5b0d9defb366432bb34134ea",
"position": {
"center": {
"x": 48.170732,
"y": 53.536585
},
"eye_left": {
"x": 38.587805,
"y": 46.830488
},
"eye_right": {
"x": 57.097317,
"y": 44.752195
},
"height": 37.804878,
"mouth_left": {
"x": 41.124878,
"y": 63.946829
},
"mouth_right": {
"x": 59.078293,
"y": 61.30439
},
"nose": {
"x": 48.540488,
"y": 56.718049
},
"width": 37.804878
},
"tag": ""
}
],
"img_height": 410,
"img_id": "e42b1354574fe1b52234fb0f88a6edfc",
"img_width": 410,
"session_id": "a8b79da2383a45b4a4b08251bd3645ef",
}
接著就可以拿string來做後續處理，比如來剖析(parse)JSON檔，讓我們可以輕易取得內容中的某個key-value。
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Comments on: "[C++] 讀取整個檔案為字串 (Read Whole File to String)" (1)
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