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I cannot find the bug.

I wrote this little code to put a few skills together to make sure I am understanding the logic correctly.
*Code runs a prompt asking for your name
*Take the name and runs a prompt to ask your age.
*I have loops set up to make sure the fields are filled out correctly, if not it re-runs the prompt.
*The prompt to ask the age, keeps looping, I have the parameters set correctly it looks like, but it won't accept any number to end the loop.

**I emboldened the few lines of code I am having an issue with.

Thanks,
Russell

Code:

var counter= 0

//declares vaule to variable

var yourName= prompt("What is your name?")

//variable created from prompt

        while(counter= 1){

//loop to run to ensure prompt is filled out

                if (yourName.length== 0) {

//condtion to check if variable has a value

        var yourName= prompt("What is your name?") 

        counter =1}

//counter set to re-run the loop if variable is blank

        



                else {

//run the new prompt once variable has a value 

                counter= 2                

                var age= prompt(yourName+ " how old are you?")} 

}

//declares value to new variable 





var counter2= 0 

        while(counter2 = 1) {

//loop to verify content of prompt is correctly filled out

                if (age <0 || age >99) {

//conditional to set parameters for the loop

                var age= prompt(yourName+ " how old are you?") 

                 counter =1} 

//sets variable counter to 1 to re-run loop

                else {

//sets counter to 2 to end loop and print a string

                 counter= 2

        document.write("Hello "+ yourName+ " I see you are"+ age+ " years old.")        

}

didnt read it all, but while(counter2 = 1) should def be while(counter2 == 1)

I did some more tinkering around with it, and I found the bug is in a different area of the code (new emboldened lines)

Code:

var counter= 0; 

//declares value to variable

var yourName= prompt("What is your name?")

//variable created from prompt

        while(counter= 1){

//loop to run to ensure prompt is filled out

                if (yourName.length== 0) {

//condition to check if variable has a value

        var yourName= prompt("What is your name?") 

        counter= 1}

//counter set to re-run the loop if variable is blank

        



                else {

//run the new prompt once variable has a value 

                counter= 2                

                var age= prompt(yourName+ " how old are you?")} 

}

//declares value to new variable 





var counter2= 0 

        while(counter2 == 1) {

                if (age <0 || age >99) {

                var age= prompt(yourName+ " how old are you?") 

                 counter =1} 

                else {

                 counter= 2

        document.write("Hello "+ yourName+ " I see you are"+ age+ " years old.")        

} 

                 }

Code:

while(counter= 1){

probably isn't doing you any favours, either

You shouldn't be using either prompt or document.write in your javaScript - those became obsolete a long time ago.

Quote:

Originally Posted by felgall (Post 1311862)

You shouldn't be using either prompt or document.write in your javaScript - those became obsolete a long time ago.

Absolutely right!

But if you insist on using prompt, here is the best way to require a valid entry-

Code:

<script type = "text/javascript">



for (var i=1; i<2; i++) {

var ans = prompt ("Enter your name here", "");

if ((ans == null ) || (ans == "") || (/[^a-z\s\-\']/gi.test(ans))) {

alert ("You must enter your name using only letters, space, hyphen and/or apostrophe!! ");

i -- ;

}

}



</script>

Likewise to require a number in range 0-100

Code:

<script type = "text/javascript">



var repeat = true;

while(repeat) {

var ans = parseFloat(prompt("Enter a positive number max.100",""));

if ((isNaN(ans)) || (ans == null) || (ans < 0) || (ans > 100)) {

alert ("You must enter a positive number max. 100");

}

else {

repeat = false;

}

}



</script>

Slightly simpler:

Code:

while( true ) 

{

    var ans = parseFloat(prompt("Enter a positive number max.100",""));

    if ((isNaN(ans)) || (ans == null) || (ans < 0) || (ans > 100)) 

    {

        alert ("You must enter a positive number max. 100");

    } else { break; }

}

Or, my preference (I don't know why...just me):

Code:

while( true ) 

{

    var age = parseInt(prompt("Enter a positive whole number max.100",""));

    if ( ! isNaN(age) && age != null && age >= 0 && age <= 100 ) { break; }

    alert ("You must enter a positive whole number max. 100");

}

I did change to parseInt since this is supposed to be getting an age.

Of course none of those approaches will prevent a visitor using any browser except Internet Explorer from simply checking the checkbox at the bottom of the prompt either on its first appearance in Opera - where it turns off JavaScript - or on its second appearance in other browsers - where it turns off all further prompts, confirms and alerts.

Thanks for the feedback yall, using values of true/false/null helped it run along with my mistakes of = instead of ==.

Code:



<html>

<script>

function nameFunction(){

var counter= 1;

//declares value to variable

var yourName= prompt("What is your name?", "Enter your name")

//variable created from prompt

        while(counter== 1){

//loop to run to ensure prompt is filled out

                if (yourName.length== 0 || yourName==="Enter your name" || yourName== null) {

//condition to check if variable has a value

        var yourName= prompt("What is your name?") 

        (counter)}

//counter set to re-run the loop if variable is blank

                        else {

//run the new prompt once variable has a value 

                (counter++)                

                var age= prompt(yourName+ " how old are you?", "Enter your age")} 

}

//declares value to new variable 

var counter2= 1

//sets a new variable to the counter

        while(counter2 == 1) {

                //counter to check new prompt 

                if (age <=0 || age >99) {

                        //parameters for new prompt

                var age= prompt(yourName+ " how old are you?") 

                 counter2 =1} 

                else {

                        //variable to end loop

                (counter2++)

        document.write("Hello "+ yourName+ ", I see you are "+ age+ " years old.")        

        //prints statement based on variable

} 

         } 

}

</script>

<body>

        <input type= "button" onclick="nameFunction()" value="Click me">

        <script>

        //links function to a button 

        </script>

</body>





</html>