Concatenating string with number in Javascript

Posted by Sparky on Stack Overflow See other posts from Stack Overflow or by Sparky
Published on 2011-01-11T13:46:31Z Indexed on 2011/01/11 13:53 UTC
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JavaScript

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string-concatenation

I'm trying to create a simple calculator in Javascript. I have an array named expression chunk[0] = 12 chunk[1] = + (the "+" sign) chunk[1] = 5

I used a for loop to loop through the chunks (chunk[]) and join then into a single expression as follows:-

equation = ""; // To make var equation a string

for(i = 0; i <= length; i++)
{
    equation = equation + expression[i];
    alert(expression[i]);
}

alert(equation);

alert(expression[i]) showed values 12, + and 5. But alert(equation) showed 125 (instead of "12+5"). I need the variable equation to be "12+5" so that I can later call eval(equation) and get the value of 12+5.

What am I doing wrong here?

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