首先,确保您已经在项目中引用了正确的命名空间。
使用ADO.NET或Entity Framework等标准数据访问技术从SQL Server中获取计数。
using System.Data.SqlClient;
using System.Data;
public int GetCountFromSQL()
{
int count = 0;
string connectionString = "Server=(localdb)\\mssqllocaldb;Database=YourDatabase;Trusted_Connection=True;";
string query = "SELECT COUNT(*) FROM YourTable";
using (SqlConnection connection = new SqlConnection(connectionString))
{
SqlCommand command = new SqlCommand(query, connection);
connection.Open();
count = (int)command.ExecuteScalar();
}
return count;
}
在Blazor中使用异步方式调用此方法,并将其返回值存储在整数变量中。
@page "/counter"
@inject IJSRuntime JsRuntime
Counter
Current count: @count
@code {
private int count = 0;
protected override async Task OnInitializedAsync()
{
count = await GetCountFromSQL();
}
private async Task IncrementCount()
{
count++;
await JsRuntime.InvokeVoidAsync("console.log", $"Count is now {count}");
}
private async Task GetCountFromSQL()
{
// Call the server-side method to get count from SQL
return await Http.GetFromJsonAsync("GetDataFromSQL");
}
}
在Blazor服务器端代码中实现GetDataFromSQL方法以返回计数值。
[HttpGet]
public async Task GetDataFromSQL()
{
int count = 0;
string connectionString = "Server=(localdb)\\mssqllocaldb;Database=YourDatabase;Trusted_Connection=True;";
string query = "SELECT COUNT(*) FROM YourTable";
using (SqlConnection connection = new