JSON.stringify(result); // object转为string
JSON.parse(str); // string转为json
=>
(x) => x + 6
相当于
function(x){
return x + 6;
};
{
"networks": {
"5777": {
"events": {},
"links": {},
"address": "0x49f62f21510b8ec6d812979b723e8f59dfa4b6de",
"transactionHash": "0xc541427f63e958db2a04d6f64ff8371d7fb8fe13f131b9732b8b66ddce4bea70"
}
}
}
var MyJson = require('./x.json')
var str = JSON.stringify(MyJson["networks"]);
var jsonStr = JSON.parse(str);
console.log("jsonStr=", jsonStr[5777].address);
console.log("jsonStr2=", MyJson["networks"]["5777"]["address"]);
...
More扩展运算符
将一个数组转为用逗号分隔的参数序列。
因为exeCommand()可以操作系统剪切板,有可能被恶意利用。所以你不能用JS“直接”调用execCommand(‘copy’),而需要放到某一个有用户出发的事件响应函数内.More
<script type="text/javascript">
function copyUrl2()
{
var Url2=document.getElementById("biao1").innerText;
var oInput = document.createElement('input');
oInput.value = Url2;
document.body.appendChild(oInput);
oInput.select(); // 选择对象
document.execCommand("Copy"); // 执行浏览器复制命令
oInput.className = 'oInput';
oInput.style.display='none';
alert('复制成功');
}
</script>
<div cols="20" id="biao1">12345678</div>
<input type="button" onClick="copyUrl2()" value="点击复制代码" />
但不支持safari浏览器。
所以使用clipboard.js
<div class="buttonClass" data-clipboard-text="
line1
line2
" data-clipboard-action="copy" id="bs">确定</div>
<script>
$('#bs').click(function () {
var roomid = 1;
var site = 'baidu.com';
var recommenCode = 'sdkc';
var clipboard = new ClipboardJS("#bs");
clipboard.on("success",function (e) {
console.info('Action:', e.action);
console.info('Text:', e.text);
console.info('Trigger:', e.trigger);
});
clipboard.on("error",function (e) {
console.error('Action:', e.action);
console.error('Trigger:', e.trigger);
console.info(e);
});
});
</script>
If you want to dynamically set a text, you’ll return a String.More
<script>
new ClipboardJS('.btn', {
text: function(trigger) {
return trigger.getAttribute('aria-label');
}
});
</script>
npm -g install js-beautify
js-beautify -f file.min.js -o file.js
var formData = new FormData();
formData.append('p1', param1);
formData.append('p2', param1);
fetch('https://url.com/index.php/', {
method: 'POST',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/x-www-form-urlencoded',
},
body: formData
})
fetch('https://mywebsite.com/endpoint/', {
method: 'POST',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
},
body: JSON.stringify({
p1: 'yourValue',
p2: 'yourOtherValue',
})
})
fetch("https://mywebsite.com/endpoint", {
method: 'GET',
headers: {
'Accept': 'application/json',
}
})
.then((response) => {
return response.json();
}).then((response) => {
console.log("response=" + JSON.stringify(response))
}
);
var CryptoJS = require("crypto-js")
var key = CryptoJS.enc.Utf8.parse("amOWLGDgZCyrG4ARTDf64Qn3FEigIQhw");
var iv = CryptoJS.enc.Utf8.parse("PPwFSQW0i7d3Unpa4ZmmILPcznV51AAa");
var encrypted = CryptoJS.AES.encrypt("message", key, {iv:iv,mode: CryptoJS.mode.CBC, padding: CryptoJS.pad.Pkcs7})
console.log("encrypted=" + encrypted.toString())
a % b = a - (a / b)*b
a % b = a & (b-1) // 当b为2^n的时候
if(str.trim()!==""){
console.log("非空");
}else{
console.log("空");
}
str.replace(new RegExp(" ",'g'), "")
const mysql = require('mysql')
const pool = mysql.createPool({
host : '127.0.0.1',
user : 'root',
password : '123456',
database : 'my_database'
})
let query = function( sql, values ) {
return new Promise(( resolve, reject ) => {
pool.getConnection(function(err, connection) {
if (err) {
reject( err )
} else {
connection.query(sql, values, ( err, rows) => {
if ( err ) {
reject( err )
} else {
resolve( rows )
}
// 结束会话
connection.release()
})
}
})
})
}
npm install minify
function requireFromString(src, filename) {
var m = new module.constructor();
m.paths = module.paths;
m._compile(src, filename);
return m.exports;
}
var codeString = fs.readFileSync("./text.js", "utf-8");
var Js = requireFromString(codeString, '')
Promise是js中的一个原生对象,是一种异步编程的解决方案,可以替换掉传统的回调函数解决方案(回调地狱)。 它通过引入一个回调,避免更多的回调。