[C#]根据索引替换字符/字符串

关键代码：

        #region 根据索引替换字符
        /// <summary>
        /// 根据索引替换字符
        /// <para>eg:Assert.AreEqual("ZBCDEFGHIJ", StringHelper.ReplaceAt("ABCDEFGHIJ",0,‘Z‘));</para>
        /// </summary>
        /// <param name="data">需要操作的字符串</param>
        /// <param name="index">目标索引</param>
        /// <param name="replace">替换成字符</param>
        /// <returns>操作后的字符串</returns>
        public static string ReplaceAt(this string data, int index, char replace)
        {
            StringBuilder _builder = new StringBuilder(data);
            _builder[index] = replace;
            return _builder.ToString();
        }
        #endregion
        #region 根据索引替换字符串
        /// <summary>
        /// 根据索引替换字符串
        /// <para>eg:Assert.AreEqual("ZXCDEFGHIJ", StringHelper.ReplaceAt("ABCDEFGHIJ", 0, 2, "ZX"));</para>
        /// </summary>
        /// <param name="data">需要操作的字符串</param>
        /// <param name="index">目标索引</param>
        /// <param name="length">需要替换长度</param>
        /// <param name="replace">替换成字符串</param>
        /// <returns>操作后的字符串</returns>
        public static string ReplaceAt(this string data, int index, int length, string replace)
        {
            StringBuilder _builder = new StringBuilder(data);
            _builder.Remove(index, length);
            _builder.Insert(index, replace);
            return _builder.ToString();
        }
        #endregion

希望有所帮助！