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POHow do I break out of recursive IEnumerable<T> loops using yield break?
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copied!<p>I have the following method that works well, except the yield break statement only breaks out of the current enumerator. I understand why this is the case, but I am drawing a blank over how to propogate the yield break up through the recursive stack.</p> <pre><code> private static IEnumerable<Node> FindChildrenById(IEnumerable nodes, string parentText) { var en = nodes.GetEnumerator(); var targetFound = false; while (en.MoveNext()) { var node = en.Current as Node; if (node != null) { if (node.Parent == null && string.IsNullOrEmpty(parentText)) { //Returns the top level nodes if an empty parentIdis entered targetFound = true; yield return node; } else if (node.Parent != null && node.Parent.Text == parentText) { //returns the nodes belonging to the parent yield return node; } else { //Recurse into the children to see whether one of these is the node to find foreach (var nd in FindChildrenById(node.Nodes, parentText)) { yield return nd; } } } } if (targetFound) { yield break; } } </code></pre> <p>So when I have the following nodes and pass "Top 2 a" as the parentText...</p> <pre><code>Top 1 Top 1 a Top 1 b Top 2 Top 2 a Top 2 aa Top 2 ab Top 2 ac Top 2 b Top 3 Top 3 a Top 3 b Top 4 </code></pre> <p>... then I get the result:</p> <pre><code>Top 2 aa Top 2 ab Top 2 ac </code></pre> <p>This is the correct result, however, when I step through my code, the outer-most loop continues to process Top 3 and Top 4. How do I break out of this outer loop?</p>

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