第一张图代码：
private void dataGridView1_CellDoubleClick(object sender, DataGridViewCellEventArgs e)
{
this.panel1.Visible = true;
this.panel2.Visible = false;
this.panel3.Visible = false;
this.panel13.Visible = false;
this.panel4.Visible = false;
this.panel12.Visible = false;
this.panel11.Visible = false;
this.panel14.Visible = false;
this.panel5.Visible = false;
this.panel6.Visible = false;
this.panel8.Visible = false;
this.panel9.Visible = false;
this.panel10.Visible = false;
this.panel7.Visible = false;
this.panel1.Size = new Size(598, 340);
this.panel1.AutoSize = true;
this.panel1.Location = new Point(0, 25);
this.panel1.Dock = DockStyle.Fill;
textBox1.Text = dataGridView1.CurrentRow.Cells[0].Value.ToString();
textBox10.Text = dataGridView1.CurrentRow.Cells[1].Value.ToString();
textBox4.Text = dataGridView1.CurrentRow.Cells[3].Value.ToString();
textBox5.Text = dataGridView1.CurrentRow.Cells[4].Value.ToString();
textBox6.Text = dataGridView1.CurrentRow.Cells[5].Value.ToString();
textBox7.Text = dataGridView1.CurrentRow.Cells[6].Value.ToString();
textBox8.Text = dataGridView1.CurrentRow.Cells[7].Value.ToString();
textBox9.Text = dataGridView1.CurrentRow.Cells[8].Value.ToString();
dateTimePicker2.Text = dataGridView1.CurrentRow.Cells[9].Value.ToString();
textBox11.Text = dataGridView1.CurrentRow.Cells[10].Value.ToString();
----》 comboBox1.Text = dataGridView1.CurrentRow.Cells[11].Value.ToString();
----》comboBox2.Text = dataGridView1.CurrentRow.Cells[12].Value.ToString();
this.textBox1.Enabled = false;
this.textBox2.Enabled = false;
this.button1.Visible = false;
this.button28.Visible = true ;
this.button29.Visible = true ;
第二张图：
---》 comboBox3.Text = dataGridView5.CurrentRow.Cells[9].Value.ToString();
打 “----》 ”处就是3个comboBox的代码，原文这个符号是没有的。
问题：代码都一样，数据库中数据类型也一样，为什么第二个图数据调不出来？
------解决思路----------------------
你comboBox3的属性是DropDownList,而不是DropDown,所以你只能赋值成下拉列表里有的选项,不能随便赋值成没有的选项
所以你必须先给它绑定数据源
------解决思路----------------------
你没给comboBox3绑定数据源,下拉框里是空的,这时你给它的text赋值,当然是不行的