利用直角坐标系和柱坐标系之间的转换关系给出了毕奥-萨伐尔定律的柱坐标表示形式，并利用该形式计算了无限长载流螺线管和无限长载流圆柱体在空间中产生的磁场分布.结果表明，毕奥-萨伐尔定律的柱坐标形式在计算具有轴对称性的载流导线产生的磁场时会更加简便.另外，还计算了载流椭圆线圈在中心轴线上的磁场分布，特别指出部分文献中提出的用坐标缩放法计算载流椭圆线圈在空间任一点的磁场分布的方法是不可行的.

The cylindrical coordinate formulation of the Biot-Savart law is derived by coordinate transformation between Cartesian and cylindrical systems. The derived formulation is applied to calculate the magnetic field distributions generated by infinitely long current-carrying solenoids and cylindrical conductors. The results demonstrate that the cylindrical coordinate representation of the Biot-Savart law significantly simplifies magnetic field calculations for current-carrying conductors with axial symmetry. Furthermore, the magnetic field distribution along the central axis of a current-carrying elliptic coil is also calculated. It is specifically noted that the coordinate scaling method proposed in some literature for calculating the magnetic field at arbitrary spatial points around such coils is unfeasible.