HTTP请求循环完成后，将执行下一个功能

Question

I need to call the next function after a loop of HTTP requests is done and the number of requests depend on the number of input.

I tried to use Promise to make sure that all HTTP requests are done . But it doesn't work.. I don't know how to solve this...

var countA,countB,countC,countD,countE,countF = 0
checkFirst(){

    Promise.all([this.checkWords()]).then( values => {
      this.doSomething()
    }
}

doSomething(){
// add value into database
}

and I need to run this function in the checkFirst() function and check it with Promise.all function..

Then, this is my HTTP request code...

checkWords(){
let promise = new Promise(function (onFulfilled, onRejected) {

  let input = "Words for send request";
  let words = ['A', 'B', 'C', 'D', 'E', 'F'];
  let wordsCount = [0, 0, 0, 0, 0, 0];
  let inputSplitted = input.split(" ", ms.length);

  for (let i = 0; i < inputSplitted.length; i++) {

    this.http.get("url + inputSplitted , options)
      .subscribe(res => {

        // content is a string that contain a word of A/B/C/D/E or F
        let content = res['_body'].entryContent
        let wordlevelIndex = 0 // For indexing "words" array
        let lvlfound = false

        while (!lvlfound) {
          // Index of the string A,B,C,D,E,F in the respond
          let strIndex = content.search(words[wordlevelIndex])
          if (strIndex == -1) { // -1 = not found A,B,C,D,E,F
            wordlevelIndex++
          } else {

            // Substring that respond for getting string A,B,C,D,E,F
            let lvlIndex = content.substring(strIndex, strIndex + 1);
            console.log(lvlIndex)

            // Count the word that found
            if (lvlIndex == words[0]){
              wordsCount[0]++
            }else if (lvlIndex == words[1]){
              wordsCount[1]++
            }else if (lvlIndex == words[2]){
              wordsCount[2]++
            }else if (lvlIndex == words[3]){
              wordsCount[3]++
            }else if (lvlIndex == words[4]){
              wordsCount[4]++
            }else if (lvlIndex == words[5]){
              wordsCount[5]++
            }
            lvlfound = true
            wordlevelIndex++
          }
        }
      });
  }
  onFulfilled([wordsCount[0], wordsCount[1], wordsCount[2], wordsCount[3], wordsCount[4], wordsCount[5]]);
  onRejected('Error');
})

promise.then(([arg0, arg1, arg2, arg3, arg4, arg5]) => {
    this.countA += arg0
    this.countB += arg1
    this.countC += arg2
    this.countD += arg3
    this.countE += arg4
    this.countF += arg5
});
    return promise
}

With these codes, I still got an asynchronous of the function which it call "this.doSomething" before all the requests is done . I only want all the responds done before using next function. Is I do something wrong via using Promise? Help me please. Thanks.

Answer 1

You're resolving (and rejecting!) the promise immediately after firing the request, way before the call returns. I think the resolution (your onFulfilled call) should be placed at the end of the subscribe argument function.