输入时自动匹配
AutoCompleteStringCollection myCutomSource = new AutoCompleteStringCollection();
myCutomSource.AddRange(new string[] { "上海市某区", "北京市某区", "天津市某区", "重庆市某区" });
this.textBox1.AutoCompleteSource = AutoCompleteSource.CustomSource;
this.textBox1.AutoCompleteMode = AutoCompleteMode.Suggest;
this.textBox1.AutoCompleteCustomSource = myCutomSource;
密码服务 passwordchar
