你调用的对象是空的。从gridView中选择任何行时出现

Question

我有2个表单.. gridForm有一个dataGridView从数据库获取数据，第二个表单editForm有textboxes类似于gridView Columns。

我想在grid中选择一行，然后点击修改按钮，必须显示editForm，文本框中包含网格值

gridForm

private void dataGridView1_CellContentClick_1(object sender, DataGridViewCellEventArgs e)
    {
        if (e.RowIndex >= 0)
        {
            DataGridViewRow row = dataGridView1.Rows[e.RowIndex];

            // when i put this line only , it works right.
            edditContactForm.edditContactNameSetter = row.Cells["contactNameGridViewColumn"].Value.ToString();

            // this also with the previous is working right too.
            edditContactForm.edditJobTitleSetter = row.Cells["jobTitleGridViewColumn"].Value.ToString();

            // the problem appears here and the exhibition shown to this line and any similar lines under it. 
            edditContactForm.edditCompanyNameSetter = row.Cells["CompanyNameGridViewColumn"].Value.ToString();
        }
    }

editForm：

    public string edditContactNameSetter 
    {
        set { txtContactName.Text = value; }
    }

    public string edditJobTitleSetter
    {
        set { txtJobTitle.Text = value; }
    }

    public string edditCompanyNameSetter
    {
        set { txtCompanyName.Text = value; }
    }

展

当我从网格中选择任何一行时，展览会出现

Answer 1

好的，我发现了问题，因为我是c＃的新手，我觉得这对专业人士来说是一个天真的错误。

问题出在SELECT FROM查询中，我只是没有从数据库中选择companyName值，因此row.Cells["CompanyNameGridViewColumn"].Value得到null。