C#：DataGridView中列类型使用时间控件和下拉列表的自动匹配

1. DataGridView中使用时间控件作为列类型

DataGridView中默认不提供DateTimePicker类型的列类型&＃xff0c;因此可以通过控件的覆盖模拟所需的功能。详细步骤如下&＃xff1a;

第一步&＃xff0c;将DataGridView单元格设置为DataGridViewTextBoxColumn类型&＃xff08;文本单元格&＃xff09;&＃xff1b;

第二步&＃xff0c;创建一个DateTimePicker控件dateTimePicker1&＃xff08;时间控件&＃xff09;&＃xff0c;Visible属性设置为false&＃xff1b;

第三步&＃xff0c;将时间控件的坐标设置为对应文本单元格的坐标&＃xff1b;

第四步&＃xff0c;若文本单元格原来为空&＃xff0c;则时间控件设置为当前时间&＃xff0c;若有值&＃xff0c;则时间控件Value属性设置为其值&＃xff1b;

第五步&＃xff0c;dateTimePicker1的ValueChanged事件和Leave事件的处理。

下面是第三步和第四步的代码&＃xff1a;

private void dataGridView1_CellDoubleClick(object sender, DataGridViewCellEventArgs e)
{// 设置坐标this.dateTimePicker1.Left &＃61; this.dataGridView1.Left &＃43; this.dataGridView1.GetCellDisplayRectangle(e.ColumnIndex, e.RowIndex, false).X;this.dateTimePicker1.Top &＃61; this.dataGridView1.Top &＃43; this.dataGridView1.GetCellDisplayRectangle(e.ColumnIndex, e.RowIndex, false).Y;// 值if (this.dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex].Value &＃61;&＃61; null || this.dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString() &＃61;&＃61; ""){this.dateTimePicker1.Value &＃61; DateTime.Now;this.dateTimePicker1.Visible &＃61; true;}else{this.dateTimePicker1.Value &＃61; Convert.ToDateTime(this.dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex].Value);this.dateTimePicker1.Visible &＃61; true;}
}第五步的代码&＃xff1a;

private void dateTimePicker1_Leave(object sender, EventArgs e)
{this.dateTimePicker1.Visible &＃61; false;//this.dataGridView1.CurrentCell.Value &＃61; this.dateTimePicker1.Value;
}private void dateTimePicker1_ValueChanged(object sender, EventArgs e)
{//this.dateTimePicker1.Visible &＃61; false;this.dataGridView1.CurrentCell.Value &＃61; this.dateTimePicker1.Value;
}

2. DataGridView中实现DataGridViewComboBoxColumn的自动匹配

这里假定已经设置了DataGridViewComboBoxColumn列的DataSource&＃xff0c;则只需在dataGridView的EditingControlShowing事件中添加相关处理逻辑。

// 显示用于编辑单元格的控件时触发
private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
{if (e.Control.GetType() &＃61;&＃61; typeof(DataGridViewComboBoxEditingControl)){//((ComboBox)e.Control).DropDownStyle &＃61; ComboBoxStyle.DropDown;ComboBox cbo &＃61; e.Control as ComboBox;cbo.DropDownStyle &＃61; ComboBoxStyle.DropDown;cbo.AutoCompleteMode &＃61; AutoCompleteMode.SuggestAppend;// 可能导致绑定多个监听函数&＃xff0c;重复执行//cbo.SelectedValueChanged &＃43;&＃61; new EventHandler(cbo_SelectedValueChanged);//Console.WriteLine(cbo.SelectedText);}}void cbo_SelectedValueChanged(object sender, EventArgs e)
{// TODO
}

注意&＃xff1a;cbo.DropDownStyle &＃61; ComboBoxStyle.DropDown;不能设置为DropDownList&＃xff0c;否则无法输入。若要求输入不能是列表之外的项&＃xff0c;则需要设置DisplayMember和ValueMember属性。比如 &＃xff0c;显示 张三、李四&＃xff0c;ValueMember保存用户id 1 2。名字是可以重复的&＃xff0c;id是唯一的。程序判断id&＃xff0c;用户看到的是名字。当把二者设为同一列&＃xff08;如上述的名字列&＃xff09;&＃xff0c;就相当于输入的与列表中的值比较&＃xff0c;若无匹配则控件会自动清空。

3. DataGridView自动滚动到最新的记录

代码如下&＃xff1a;

// 滚动条滚动到最后
if (this.dataGridView1.Rows.Count >&＃61; 1)
{this.dataGridView1.FirstDisplayedScrollingRowIndex &＃61; this.dataGridView1.Rows.Count - 1;
}