StackOverflow2013

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copied!<p>I'm legitimately curious at how you would load the values of a class without using reflection unless you had methods hardcoded to accomplish it. I'm sure there's another answer, but I'm not too ashamed to say I do not have experience in it. As for something I wrote to auto-load data, I have two base data classes I work from: a single object and then a list. In the single object (BaseDataClass), I have this method.</p> <pre><code> public virtual void InitializeClass(DataRow dr) { Type type = this.GetType(); PropertyInfo[] propInfos = type.GetProperties(); for (int i = 0; i < dr.ItemArray.GetLength(0); i++) { if (dr[i].GetType() != typeof(DBNull)) { string field = dr.Table.Columns[i].ColumnName; foreach (PropertyInfo propInfo in propInfos) { if (field.ToLower() == propInfo.Name.ToLower()) { // get data value, set property, break object o = dr[i]; propInfo.SetValue(this, o, null); break; } } } } } </code></pre> <p>And then in the data list </p> <pre><code>public abstract class GenericDataList<T> : List<T> where T : BaseDataClass { protected void InitializeList(string sql) { DataHandler dh = new DataHandler(); // my general database class DataTable dt = dh.RetrieveData(sql); if (dt != null) { this.InitializeList(dt); dt.Dispose(); } dt = null; dh = null; } protected void InitializeList(DataTable dt) { if (dt != null) { Type type = typeof(T); MethodInfo methodInfo = type.GetMethod("InitializeClass"); foreach (DataRow dr in dt.Rows) { T t = Activator.CreateInstance<T>(); if (methodInfo != null) { object[] paramArray = new object[1]; paramArray[0] = dr; methodInfo.Invoke(t, paramArray); } this.Add(t); } } } } </code></pre> <p>I'm open to criticism, because no one has ever reviewed this code before. I am the sole programmer where I work, so I do not have others to bounce ideas off of. Thankfully, now I've come across this website!</p> <p>Edit: You know what? Looking at it now, I don't see why I shouldn't just rewrite that last method as </p> <pre><code> protected void InitializeList(DataTable dt) { if (dt != null) { Type type = typeof(T); foreach (DataRow dr in dt.Rows) { T t = Activator.CreateInstance<T>(); (t as BaseDataClass).InitializeClass(dr); this.Add(t); } } } </code></pre> <p>I assume that works, although I haven't tested it. No need to use reflection on that part.</p>

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