javascript 如果变量为真
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javascript If Variable(s) is True
提问by coffeemonitor
I'm not sure if I'm misunderstanding how True/False works in Javascript or not. In my Jquery script below I'm declaring 6 variables as false. If the regex validation conditions are good, then I redeclare the variable(s) to true. On the bottom is a simple alert() to tell me when all variables are true.
我不确定我是否误解了 True/False 在 Javascript 中是如何工作的。在下面的 Jquery 脚本中，我将 6 个变量声明为 false。如果正则表达式验证条件良好，那么我将变量重新声明为真。底部是一个简单的 alert() 来告诉我所有变量何时都为真。
The validation conditions are working (removing/adding classes), but the alert does not show up. That's why I'm not sure if I'm messing up the true/false part or not.
验证条件有效（删除/添加类），但未显示警报。这就是为什么我不确定我是否搞砸了真/假部分。
$('#password1').keyup(function() {
var checkLength = false;
var checkLetter = false;
var checkCaps = false;
var checkNum = false;
var checkSymbol = false;
var checkSpace = false;
var pswd = $(this).val();
//validate the length
if(pswd.length < 6 ){
$('#length').removeClass('valid').addClass('invalid');
}else{
$('#length').removeClass('invalid').addClass('valid');
checkLength = true;
}
//validate letter
if(pswd.match(/[A-Za-z]/)){
$('#letter').removeClass('invalid').addClass('valid');
}else{
$('#letter').removeClass('valid').addClass('invalid');
checkLetter = true;
}
//validate capital letter
if(pswd.match(/[A-Z]/)){
$('#capital').removeClass('invalid').addClass('valid');
}else{
$('#capital').removeClass('valid').addClass('invalid');
checkCaps = true;
}
//validate number
if(pswd.match(/\d/)){
$('#number').removeClass('invalid').addClass('valid');
}else{
$('#number').removeClass('valid').addClass('invalid');
checkNum = true;
}
//validate symbols
if(pswd.match(/[^a-zA-Z0-9]/)){
$('#symbol').removeClass('invalid').addClass('valid');
}else{
$('#symbol').removeClass('valid').addClass('invalid');
checkSymbol = true;
}
//validate no spaces
if(pswd.match(/\s/)){
$('#spaces').removeClass('valid').addClass('invalid');
}else{
$('#spaces').removeClass('invalid').addClass('valid');
checkSpace = true;
}
// here is where I'm concerned I'm wrong
if(checkLength == true && checkLetter == true && checkCaps == true && checkNum == true && checkSymbol == true && checkSpace == true){
alert("All good");
}
});
Would someone double check me?
有人会仔细检查我吗？
回答by Christoph
At first, there is no need to write checkLength == true, checkLengthis enough since they are all boolean variables.
一开始不需要写checkLength == true,checkLength就够了，因为它们都是布尔变量。
Second, in some of your conditions you assign class invalidbut set the var to true, while in others you do it vice versa. Every check... = trueshould be in the same branch with class = valid.
Also, personally, I would adapt the validity conditions, to have all positive events either in the ifor in the elsebranch, but not mixed like you do at the moment.
Lastly, I always try to avoid duplicate code. There are a lot of places you could refactor, but you could start easy with setting the classes in a separate function.
其次，在您的某些情况下，您分配 classinvalid但将 var 设置为 true，而在其他情况下，您则相反。每个都check... = true应该与class = valid. 此外，就个人而言，我会调整有效性条件，以if在else分支中或在分支中包含所有正面事件，但不会像您目前那样混合。最后，我总是尽量避免重复代码。有很多地方可以重构，但可以从在单独的函数中设置类开始。
See it working in this fiddle.
看到它在这个 fiddle 中工作。
$('#password1').keyup(function() {
var checkLength = false;
var checkLetter = false;
var checkCaps = false;
var checkNum = false;
var checkSymbol = false;
var checkSpace = false;
var pswd = $(this).val();
//validate the length
// reverse the condition, to have the valid state in the if branch as well
if(pswd.length >= 6 ){
setValid('#length');
checkLength = true;
}else{
setInvalid('#length');
}
//validate letter
if(pswd.match(/[A-Za-z]/)){
setValid('#letter');
checkLetter = true;
}else{
setInvalid('#letter');
}
//validate capital letter
if(pswd.match(/[A-Z]/)){
setValid('#capital');
checkCaps = true;
}else{
setInvalid('#capital');
}
//validate number
if(pswd.match(/\d/)){
setValid('#number');
checkNum = true;
}else{
setInvalid('#number');
}
//validate symbols
if(pswd.match(/[^a-zA-Z0-9]/)){
setValid('#symbol');
checkSymbol = true;
}else{
setInvalid('#symbol');
}
//validate no spaces
if(!pswd.match(/\s/)){
setValid('#spaces');
checkSpace = true;
}else{
setInvalid('#spaces');
}
function setValid(e){$(e).removeClass('invalid').addClass('valid')}
function setInvalid(e){$(e).removeClass('valid').addClass('invalid')}
if(checkLength && checkLetter && checkCaps && checkNum && checkSymbol && checkSpace){
alert("All good");
}
console.log("keyup");
});<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input id="password1" type="text">回答by coffeemonitor
All of these have check* = truein the wrong place:
所有这些都check* = true在错误的地方：
//validate letter
if(pswd.match(/[A-Za-z]/)){
$('#letter').removeClass('invalid').addClass('valid');
}else{
$('#letter').removeClass('valid').addClass('invalid');
checkLetter = true;
}
//validate capital letter
if(pswd.match(/[A-Z]/)){
$('#capital').removeClass('invalid').addClass('valid');
}else{
$('#capital').removeClass('valid').addClass('invalid');
checkCaps = true;
}
//validate number
if(pswd.match(/\d/)){
$('#number').removeClass('invalid').addClass('valid');
}else{
$('#number').removeClass('valid').addClass('invalid');
checkNum = true;
}
//validate symbols
if(pswd.match(/[^a-zA-Z0-9]/)){
$('#symbol').removeClass('invalid').addClass('valid');
}else{
$('#symbol').removeClass('valid').addClass('invalid');
checkSymbol = true;
}
Insert the statements in the block following the if(where they are deemed valid) as opposed to in the else(where they are deemed invalid):
将语句插入if（在它们被视为有效的地方）而不是在else（它们被视为无效的地方）之后的块中：
//validate letter
if(pswd.match(/[A-Za-z]/)){
$('#letter').removeClass('invalid').addClass('valid');
checkLetter = true;
}else{
$('#letter').removeClass('valid').addClass('invalid');
}
//validate capital letter
if(pswd.match(/[A-Z]/)){
$('#capital').removeClass('invalid').addClass('valid');
checkCaps = true;
}else{
$('#capital').removeClass('valid').addClass('invalid');
}
//validate number
if(pswd.match(/\d/)){
$('#number').removeClass('invalid').addClass('valid');
}else{
$('#number').removeClass('valid').addClass('invalid');
checkNum = true;
}
//validate symbols
if(pswd.match(/[^a-zA-Z0-9]/)){
$('#symbol').removeClass('invalid').addClass('valid');
checkSymbol = true;
}else{
$('#symbol').removeClass('valid').addClass('invalid');
}
And, although there are better ways of writing validation, this is a similar, yet more concise version of your snippet:
而且，虽然有更好的编写验证的方法，但这是您代码段的类似但更简洁的版本：
$("#password1").keyup(function() {
var pswd = $(this).val();
var checkLength = pswd.length >= 6;
var checkLetter = /[A-Za-z]/.test(pswd);
var checkCaps = /[A-Z]/.test(pswd);
var checkNum = /\d/.test(pswd);
var checkSymbol = /[^A-Za-z0-9]/.test(pswd);
var checkSpace = !/\s/.test(pswd);
$("#length") .removeClass("valid invalid").addClass(checkLength ? "valid" : "invalid");
$("#letter") .removeClass("valid invalid").addClass(checkLetter ? "valid" : "invalid");
$("#capital").removeClass("valid invalid").addClass(checkCaps ? "valid" : "invalid");
$("#number") .removeClass("valid invalid").addClass(checkNum ? "valid" : "invalid");
$("#symbol") .removeClass("valid invalid").addClass(checkSymbol ? "valid" : "invalid");
$("#spaces") .removeClass("valid invalid").addClass(checkSpace ? "valid" : "invalid");
if(checkLength && checkLetter && checkCaps && checkNum && checkSymbol && checkSpace) {
alert("All good");
}
});
回答by Brian J
To me, it seems that your assignments are valid statements. Whether or not they are getting set the way you want is a different matter.
在我看来，您的作业似乎是有效的陈述。他们是否按照您想要的方式进行设置是另一回事。
It is most likely that one of the flags is not being set the way you want it to be set. To check this, you could alert each of your flags (checkCaps, etc) to confirm that each value is set the way you want. If all of the true/false is correct, then the issue would be in your final if statement.
很可能其中一个标志没有按照您希望的方式设置。要检查这一点，您可以提醒每个标志（checkCaps 等）以确认每个值都按照您想要的方式设置。如果所有真/假都是正确的，那么问题将出现在您的最终 if 语句中。
As many people have suggested, removing the == trueis a good idea. Since Javascript is dynamically typed, there is a slightpossibility that it is not treating your flags as a boolean, but as something else.
正如许多人所建议的那样，删除== true是一个好主意。由于JavaScript是动态类型的，有一个轻微的，它不是治疗你的标志为一个布尔可能性，但别的东西。
If removing the == truedoes not work, you could check different pairs of flags to see which one makes the entire statement false.
如果删除== true不起作用，您可以检查不同的标志对以查看哪一个使整个语句为假。
