（1）三个效果
1>传的参数较多，对数据表无要求，但可以设置下拉列的宽度和标题
2>传的参数很少，对数据表有要求(必须是处理好的)
3>传的参数一般，对数据表无要求，但不可以设置下拉列的宽度和标题
1）
2）
3）
（2）后台代码
底层类：
/// <summary>/// 初始化LookUpEdit控件 (加载数据表中的一列或多列，，且显示下拉列标题，可以设置下拉列的宽度)/// </summary>/// <param name="lookUpEdit">空间名称</param>/// <param name="fields">下拉要显示的列</param>/// <param name="captions">下拉要显示的列标题</param>/// <param name="widths">下拉显示列的宽度 如果null 宽度为系统默认 </param>/// <param name="dt">绑定的数据表</param>/// <param name="valueMember">绑定列</param>/// <param name="displayMember">显示列</param>/// <param name="dropDownRows">下拉最多显示个数 如果为0，显示全部</param>public static void InitLookUpEdit(DevExpress.XtraEditors.LookUpEdit lookUpEdit,string[] fields, string[] captions, int[] widths,DataTable dt, string valueMember, string displayMember, int dropDownRows){lookUpEdit.Properties.NullText = "—请选择—";lookUpEdit.Properties.Columns.Clear();if (fields.Length != captions.Length){return;}for (int i = 0; i < fields.Length; i++){if (widths != null){if (fields.Length != widths.Length){return;}lookUpEdit.Properties.Columns.Add(new DevExpress.XtraEditors.Controls.LookUpColumnInfo(fields[i], widths[i], captions[i]));lookUpEdit.Properties.Columns[i].Visible = widths[i] == 0 ? false : true;}else{lookUpEdit.Properties.Columns.Add(new DevExpress.XtraEditors.Controls.LookUpColumnInfo(fields[i], captions[i]));}lookUpEdit.Properties.Columns[i].Alignment = DevExpress.Utils.HorzAlignment.Center;}if (widths == null)lookUpEdit.Properties.Columns[valueMember].Visible = false;lookUpEdit.Properties.DataSource = dt;lookUpEdit.Properties.ValueMember = valueMember;lookUpEdit.Properties.DisplayMember = displayMember;lookUpEdit.Properties.ShowHeader = true;lookUpEdit.Properties.ShowFooter = false;if (dropDownRows == 0){lookUpEdit.Properties.DropDownRows = dt.Rows.Count + 1;}else{lookUpEdit.Properties.DropDownRows = dt.Rows.Count > dropDownRows ? dropDownRows : dt.Rows.Count;}}/// <summary>/// 初始化LookUpEdit控件 (下拉加载数据表中的所有列，且不显示下拉列标题、不设置宽度)/// </summary>/// <param name="lookUpEdit">控件名称</param>/// <param name="dt">绑定的数据表</param>/// <param name="valueMember">绑定列</param>/// <param name="displayMember">显示列</param>/// <param name="dropDownRows">下拉最多显示个数 如果为0，显示全部</param>public static void InitLookUpEdit(DevExpress.XtraEditors.LookUpEdit lookUpEdit,DataTable dt, string valueMember, string displayMember, int dropDownRows){if (!dt.Columns.Contains(valueMember) && dt.Columns.Contains(displayMember)){return;}lookUpEdit.Properties.NullText = "—请选择—";lookUpEdit.Properties.Columns.Clear();foreach (DataColumn col in dt.Columns)lookUpEdit.Properties.Columns.Add(new DevExpress.XtraEditors.Controls.LookUpColumnInfo(col.ColumnName));lookUpEdit.Properties.DataSource = dt;lookUpEdit.Properties.Columns[valueMember].Visible = false;lookUpEdit.Properties.ValueMember = valueMember;lookUpEdit.Properties.DisplayMember = displayMember;lookUpEdit.Properties.ShowHeader = false;lookUpEdit.Properties.ShowFooter = false;if (dropDownRows == 0){lookUpEdit.Properties.DropDownRows = dt.Rows.Count;}else{lookUpEdit.Properties.DropDownRows = dt.Rows.Count > dropDownRows ? dropDownRows : dt.Rows.Count;}}/// <summary>/// 初始化LookUpEdit控件 (下拉加载数据表中一列或多列，且不显示下拉列标题、不设置宽度)/// </summary>/// <param name="lookUpEdit">控件名称</param>/// <param name="dt">绑定的数据表</param>/// <param name="fields">下拉要显示的列(要包含绑定列)</param>/// <param name="valueMember">绑定列</param>/// <param name="displayMember">显示列</param>/// <param name="dropDownRows">下拉最多显示个数 如果为0，显示全部</param>public static void InitLookUpEdit(DevExpress.XtraEditors.LookUpEdit lookUpEdit,DataTable dt, string[] fields, string valueMember, string displayMember, int dropDownRows){//数据表中是否存在fields的列if (fields != null){for (int i = 0; i < fields.Length; i++){if (!dt.Columns.Contains(fields[i])){MessageBox.Show("LookUpEdit控件 列名不在数据表中");return;}}}//过滤列 且去掉重复DataView dv = new DataView(dt);dt = dv.ToTable(true, fields);InitLookUpEdit(lookUpEdit, dt, valueMember, displayMember, dropDownRows);}三亚呀——赴一个蓝天碧海。只是微笑地固执自己的坚持，
