javascript - 我的代码中的 Var 不起作用

Question

我的代码中的“Var”不起作用。 它总是显示'hasclass = 0 and body has class'，但应该hasclass = yes and body has class

setInterval(function() {
if($('.webMessengerMessageGroup').length>0) {
    if(hasclass === 'dooainn') {
        console.log('hasclass = yes and body has class');
    } else {
        var hasclass = 'dooainn';
        console.log('hasclass = 0 and body has class'); 
        $('._38 p').click(function () {
            var message_text = $(this).text();
            console.log(message_text);
        });
    }
} else {
    console.log('body has not class');
} 
},2000);

Answer 1

var hasclass 未在 if 范围内定义。如果将 var 移到函数之外，如下所示，它应该可以工作。

var hasclass = '';
setInterval(function() {
if($('.webMessengerMessageGroup').length>0) {
    if(hasclass === 'dooainn') {
        console.log('hasclass = yes and body has class');
    } else {
        hasclass = 'dooainn';
        console.log('hasclass = 0 and body has class'); 
        $('._38 p').click(function () {
            var message_text = $(this).text();
            console.log(message_text);
        });
    }
} else {
    console.log('body has not class');
} 
},2000);