c# - 如何向绑定(bind)到实体的组合框添加新项目？

Question

C#生成的设计类:

    // 
    // usepurposeComboBox
    // 
    this.usepurposeComboBox.DataSource = this.usepurposeBindingSource;
    this.usepurposeComboBox.DisplayMember = "Name";
    this.usepurposeComboBox.FormattingEnabled = true;
    this.usepurposeComboBox.Location = new System.Drawing.Point(277, 53);
    this.usepurposeComboBox.Name = "usepurposeComboBox";
    this.usepurposeComboBox.Size = new System.Drawing.Size(218, 21);
    this.usepurposeComboBox.TabIndex = 4;
    this.usepurposeComboBox.ValueMember = "id";
    // 
    // usepurposeBindingSource
    // 
    this.usepurposeBindingSource.DataSource = typeof(mydatabaseEntities.usepurpose);

然后我将 BindingSource (usepurposeBindingSource) 绑定(bind)到实体:

usepurposeBindingSource.DataSource = mydatabaseEntities.usepurposes;

而且我无法向 usepurposeComboBox 添加新行，因为它已被绑定(bind)。有解决方法吗？

Answer 1

最短的方法是向您的 dataTable 添加一个新行，然后像这样将您的组合框绑定(bind)到它:

公司补偿 = new Company();

        //pupulate dataTable with data
        DataTable DT = comps.getCompaniesList();

        //create a new row
        DataRow DR = DT.NewRow();
        DR["c_ID"] = 0;
        DR["name"] = "Add new Company";
        DR["country"] = "IR";

        //add new row to data table
        DT.Rows.Add(DR);

        //Binding DataTable to cxbxCompany
        cxbxCompany.DataSource = DT;
        cxbxCompany.DisplayMember = "name";
        cxbxCompany.ValueMember = "c_ID";