javascript convert array to string

Question

Hello i have 2 arrays and and i want to put them in a single string. My arrays can take values from 0 to a maxNum-1. So lets say i have myArray1[i] and myArray2[i] I want to make a string like this:

string = "myArray1ID" + 1 + "=" + (myArray1[1])
 + "&" +"myArray2ID" + 1 + "=" + (myArray2[1])
 + "&" + "myArray1ID" + 2 + "=" + (myArray1[2])
 + "&" + "myArray2ID" + 2 + "=" + (myArray2[2])
 + ......
 + "myArray1ID" + (maxNum - 1) + "=" + (myArray[maxNum-1])
 + "&" "myArray2ID" + (maxNum - 1) + "=" + (myArray2[maxNum-1]);

Is it possible?

• Scott Stevens: Do you have myarray[0] and my2ndarray[0]? E.g. Are there duplicate keys?
• gdoron: Yes, it's possible, what have you tried?
• meo: yes it is, you just did :) why cant you just loop those arrays?

Answer 1

Use the power of loops.

var output = [];
for (var i = 1; i < maxNum; ++i) {
 output.push(
 'myArray1ID' + i + '=' + myArray1[i],
 'myArray2ID' + i + '=' + myArray2[i]
 );
}
return output.join('&');

Answer 2

var myString = '';
for(var i; i < myArray1.length; i++){
 myString += "myArray1ID" + i + "=" + (myArray1[i]) + "&";
 myString += "myArray2ID" + i + "=" + (myArray2[i]) + "&";
}
//remove trialing "&"
var myString = myString.substring(0, myString.length-1);

This assumes that both arrays are of equal length

Answer 3

Use a loop :

var stringArray = sep = ""; 
for(var i = 1; i < maxNum; i++) {
 stringArray += sep + "myArray1ID" + i + "=" + myArray1[i];
 stringArray += "&myArray2ID" + i + "=" + myArray2[i];
 sep = "&";
}

The var stringArray should contains your array values.

• Scott: In this example, the variable 'sep' will be leaked to the global scope. Unless that's your intention, the two variables 'stringArray' and 'sep' should be defined individually. Also, nickf's answer will be more performant, array operations are generally faster than string concatenation.