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POJavascript: Initializing a variable from a string?
 

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  1. POJavascript: Initializing a variable from a string?
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    <p>I am working in Google Maps and have three+ tile overlays to create. An example:</p> <p><strong>Tile Overlay</strong></p> <pre><code>var parkingOptions = { //Parking Overlay getTileUrl: function(coord, zoom) { return "/maps/tiles/tilesparking/" + zoom + "_" + coord.x + "_" + coord.y + ".png"; }, tileSize: new google.maps.Size(256, 256) }; var parkingMapType = new google.maps.ImageMapType(parkingOptions); </code></pre> <p>However, to avoid 404 errors by missing tiles outside of my mapping range, my code is a little more complex; thus, I intended to make a loop where a specific keyword assigned to each overlay <em>(here given as "parking")</em> would be inserted into the above code. Thus:</p> <p><strong>For Loop</strong></p> <pre><code>var tileNames = ["base", "parking", "access"]; for (var i = 0; i &lt; tileNames.length; i++) { //insert Tile Overlay code here }; </code></pre> <p>However, I have one particular issue: I can not find a way to take the string from the tileNames array and use them in initializing the two variables in the Tile Overlay code. Ideally, I would like to achieve something like this:</p> <p><strong>Attempt 1</strong></p> <pre><code>var tileNames[1] + "Options" = { //ideally: var parkingOptions = { //insert remaining code }; </code></pre> <p>However this doesn't work, nor did I really expect it to. Neither would trying to create those full strings and trying to insert it into the initialization:</p> <p><strong>Attempt 2</strong></p> <pre><code>var newOptions = tileNames[1] + "Options"; var newOptions = { //insert remaining code }; </code></pre> <p>Thus, is there a way to do place a string into initializing variables?</p> <hr> <p><strong>Note:</strong> I have included my own alternative solution to the problem as an answer. It should work, but it destroys the names of the variables and replaces it with a nondescript array variable. I preferably would like to retain a descriptive variable name as they are used often in adding and hiding the overlays in the resulting code.</p> <hr> <p><strong>Solution</strong> <em>For this question anyways...</em></p> <pre><code>var tileNames = ["beloit", "parking", "access"]; var mapType = {}; for (var i = 0; i &lt; tileNames.length; i++) { var tileOptions = { getTileUrl: function(coord, zoom) { return "/maps/tiles/tiles" + tileNames[i] + "/" + zoom + "_" + coord.x + "_" + coord.y + ".png"; }, tileSize: new google.maps.Size(256, 256) }; mapType[tileNames[i]] = new google.maps.ImageMapType(tileOptions); }; </code></pre> <p>The other part of the puzzle, the "tileNames[i]" in the getTileUrl function is undefined because the function wants it when it is executed rather than placing the name string into the function; however, that is a new question to be found here: <a href="https://stackoverflow.com/questions/11214807/javascript-using-a-string-to-define-a-function">Javascript: Making a variable static when defining a function in a loop?</a></p>
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