[英]how to change the value of variable after calling the function using tablesasjson?
為什么調用函數后變量不能改變?
這是我的代碼:
const tabletojson = require('tabletojson');
var email ;
tabletojson.convertUrl(
'https://myurl
,
{ stripHtmlFromCells: true },
function(tablesAsJson) {
email = tablesAsJson[2][7][1];
var result2 = tablesAsJson;
console.log(result2);
var Firstname;
var lastname;
Firstname = tablesAsJson[0][1][1]
lastname = tablesAsJson[0][0][1]
console.log("Hello Sir: "+Firstname + " " +lastname + ". your email is : " + email)
console.log(email)// this prints the correct answer
}
);
在嘗試在函數范圍外打印電子郵件時,它返回一個空白文本,console.log("the email is " + email);
如果您需要將此代碼用作模塊的導出函數,則需要如下內容:
測試模塊.js:
'use strict';
const tabletojson = require('tabletojson');
async function getTableAsArray(url) {
try {
return await tabletojson.convertUrl(url);
} catch (err) {
console.error(err);
}
}
module.exports = {
getTableAsArray,
};
測試.js:
'use strict';
const testModule = require('./test-module.js');
(async function main() {
try {
const array = await testModule.getTableAsArray(
'https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes'
);
console.log(array[1][0]);
} catch (err) {
console.error(err);
}
})();
方法 convertUrl 是異步的,您不能隨意在頂級代碼中使用像await 。
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