elementUI switch displays text internally

Just add some css

/deep/ .el-switch__core::before {
    content: "高";
    position: absolute;
    top: 0;
    right: 5px;
    color: #fff;
  }
  .is-checked /deep/ .el-switch__core::before {
    content: "低";
    position: absolute;
    top: 0;
    left: 5px;
    color: #fff;
  }