function createErrorMessage(errorMessage) {
	var errorMessage_array = errorMessage.split("|");
	document.getElementById("errorMsg").style.display='block';
	document.getElementById("errorMsg_head").innerHTML = errorMessage_array[0];
	document.getElementById("errorMsg_body").innerHTML = errorMessage_array[1];
	document.getElementById("errorMsg_button").value = errorMessage_array[2];
}

function validateForm(formContainer,requiredFields,errorMessage)
{
	var valid = true;

	// Split list of required fields into an array
	var requiredFields_array = requiredFields.split(",");

	for(i=0; i<document.getElementsByName("SndMail").length; i++) {
		if(document.getElementsByName("SndMail")[i].parentNode.parentNode.id == formContainer) {
			var path = document.getElementsByName("SndMail")[i];
		}
	}

	// Check the value of each required field by looping through the array that was created earlier
	for(i=0; i<requiredFields_array.length; i++)
	{
		if(path.elements[requiredFields_array[i]].value.length == 0)
		{
			// Call upon a function that displays an error message,
			// which can be a simple alert box or a custom-made message by using the function createErrorMessage.

			createErrorMessage(errorMessage);

			// Cancel form submission
			valid = false; break;
		}
	}
	return valid;
}