This article demonstrates how to protect or unprotect Excel worksheet using the WorksheetApi interface provided by Spire.Cloud.Excel.

Protect Excel worksheet

using Spire.Cloud.Excel.Sdk.Api;
using Spire.Cloud.Excel.Sdk.Client;
using Spire.Cloud.Excel.Sdk.Model;
using System;

namespace ProtectWorksheet
{
    class Program
    {
        static String appId = "App ID";
        static String appKey = "App Key";
        static String baseUrl = "https://api.cloudxdocs.com";

        //Create a Configuration instance based on App ID, App Key and base URL
        static Configuration configuration = new Configuration(appId, appKey, baseUrl);

        //Create a WorksheetApi instance
        static WorksheetsApi worksheetsApi = new WorksheetsApi(configuration);
        static void Main(string[] args)
        {
            //Specify the input document
            string name = "sample.xlsx";
            //Specify the folder storing the input document, and it's "null" if nothing
            string folder = "input";
            //Use the 2G storage provided by E-iceblue, and it's "null" by default
            string storage = null;
            //Specify the name of the worksheet that you want to protect
            string sheetName = "Sheet1";
            //Create a ProtectSheetParameter instance
            ProtectSheetParameter protectParameter = new ProtectSheetParameter();
            //Set password to protect the worksheet
            protectParameter.Password = "123";
            //Set protection type
            protectParameter.ProtectionType = "scenarios";
            //Allow selecting locked cell
            protectParameter.AllowSelectingLockedCell = "true";
            //Allow deleting column
            protectParameter.AllowDeletingColumn = "true";
            //Allow formatting row
            protectParameter.AllowFormattingRow = "true";

            //Call ProtectWorksheet method to protect the worksheet
            worksheetsApi.ProtectWorksheet(name, sheetName, protectParameter, folder, storage);
        }
    }
}

Output:

Unprotect Excel worksheet

using Spire.Cloud.Excel.Sdk.Api;
using Spire.Cloud.Excel.Sdk.Client;
using Spire.Cloud.Excel.Sdk.Model;
using System;

namespace UnprotectWorksheet
{
    class Program
    {
        static String appId = "APP ID";
        static String appKey = "APP Key";
        static String baseUrl = "https://api.cloudxdocs.com";

        //Create a Configuration instance based on App ID, App Key and base URL
        static Configuration configuration = new Configuration(appId, appKey, baseUrl);

        //Create a WorksheetApi instance
        static WorksheetsApi worksheetsApi = new WorksheetsApi(configuration);
        static void Main(string[] args)
        {
            //Specify the input document
            string name = "sample.xlsx";
            //Specify the folder storing the input document, and it's "null" if nothing
            string folder = "input";
            //Use the 2G storage provided by E-iceblue, and it's "null" by default
            string storage = null;
            //Specify the name of the worksheet that you want to unprotect
            string sheetName = "Sheet1";
            //Create a ProtectSheetParameter instance
            ProtectSheetParameter protectParameter = new ProtectSheetParameter();
            //Set password to unprotect the worksheet
            protectParameter.Password = "123";
            //Call UnProtectWorksheet method to unprotect the worksheet
            worksheetsApi.UnProtectWorksheet(name, sheetName, protectParameter, folder, storage);
        }
    }
}