el-form 嵌套 el-table 树形结构中多个 children 表单的必填校验

在 el-form 嵌套 el-table 树形结构中，若存在多个 children 表单且需要进行必填校验，可以按照以下步骤进行操作：

1. 在 el-table 中绑定 row-key 属性，确保每个子节点都有一个唯一的标识符。

2. 在 el-form 中添加 ref 属性，方便在代码中调用。

3. 在 el-table 中，为每个子节点的表单数据添加一个字段，例如 requiredFields，用于记录该节点下必填字段的状态。

4. 在 el-form 中，为每个必填的表单元素添加 v-model 和 ref 属性，并在其后面添加一个自定义的校验函数。

5. 在校验函数中，通过 ref 属性获取到 el-table 中的所有子节点的必填状态，如果存在必填字段未填写，则返回一个错误提示。

6. 在提交表单时，调用 el-form 的 validate 方法，进行表单校验。

以下是示例代码：

<template>
  <el-form ref="form" :model="formData" :rules="rules">
    <el-table :data="tableData" :row-key="rowKey">
      <el-table-column prop="name" label="名称"></el-table-column>
      <el-table-column prop="age" label="年龄"></el-table-column>
      <el-table-column label="子节点">
        <template slot-scope="{ row }">
          <el-table :data="row.children" :row-key="rowKey">
            <el-table-column prop="name" label="名称"></el-table-column>
            <el-table-column prop="age" label="年龄"></el-table-column>
            <el-table-column label="表单">
              <template slot-scope="{ row: child }">
                <el-form :model="child.formData" :rules="child.rules">
                  <el-form-item label="姓名" prop="name">
                    <el-input v-model="child.formData.name" ref="nameInput" @blur="validateChild(child)"></el-input>
                  </el-form-item>
                  <el-form-item label="年龄" prop="age">
                    <el-input v-model="child.formData.age" ref="ageInput" @blur="validateChild(child)"></el-input>
                  </el-form-item>
                </el-form>
              </template>
            </el-table-column>
          </el-table>
        </template>
      </el-table-column>
    </el-table>
    <el-button type="primary" @click="submitForm">提交</el-button>
  </el-form>
</template>

<script>
export default {
  data() {
    return {
      formData: {
        name: '',
        age: '',
        children: [
          {
            name: '子节点1',
            age: '',
            requiredFields: {
              name: false,
              age: true,
            },
            formData: {
              name: '',
              age: '',
            },
            rules: {
              name: [
                { required: true, message: '姓名不能为空', trigger: 'blur' },
              ],
              age: [
                { required: true, message: '年龄不能为空', trigger: 'blur' },
              ],
            },
            children: [],
          },
          {
            name: '子节点2',
            age: '',
            requiredFields: {
              name: true,
              age: false,
            },
            formData: {
              name: '',
              age: '',
            },
            rules: {
              name: [
                { required: true, message: '姓名不能为空', trigger: 'blur' },
              ],
              age: [
                { required: true, message: '年龄不能为空', trigger: 'blur' },
              ],
            },
            children: [],
          },
        ],
      },
      rules: {
        name: [
          { required: true, message: '姓名不能为空', trigger: 'blur' },
        ],
        age: [
          { required: true, message: '年龄不能为空', trigger: 'blur' },
        ],
      },
      tableData: [
        {
          name: '节点1',
          age: '',
          children: [
            {
              name: '子节点1',
              age: '',
              requiredFields: {
                name: false,
                age: true,
              },
              formData: {
                name: '',
                age: '',
              },
              rules: {
                name: [
                  { required: true, message: '姓名不能为空', trigger: 'blur' },
                ],
                age: [
                  { required: true, message: '年龄不能为空', trigger: 'blur' },
                ],
              },
              children: [],
            },
          ],
        },
        {
          name: '节点2',
          age: '',
          children: [
            {
              name: '子节点2',
              age: '',
              requiredFields: {
                name: true,
                age: false,
              },
              formData: {
                name: '',
                age: '',
              },
              rules: {
                name: [
                  { required: true, message: '姓名不能为空', trigger: 'blur' },
                ],
                age: [
                  { required: true, message: '年龄不能为空', trigger: 'blur' },
                ],
              },
              children: [],
            },
          ],
        },
      ],
    };
  },
  methods: {
    rowKey(row) {
      return row.name;
    },
    validateChild(child) {
      const errors = [];
      if (!child.formData.name) {
        errors.push('姓名不能为空');
      }
      if (!child.formData.age) {
        errors.push('年龄不能为空');
      }
      child.requiredFields.name = !child.formData.name;
      child.requiredFields.age = !child.formData.age;
      this.$nextTick(() => {
        this.validateRequiredFields();
      });
      return errors;
    },
    validateRequiredFields() {
      const errors = [];
      const nameInputs = this.$refs.form.$el.querySelectorAll('.el-form-item__error[name="name"]');
      const ageInputs = this.$refs.form.$el.querySelectorAll('.el-form-item__error[name="age"]');
      this.formData.children.forEach((node) => {
        if (node.requiredFields.name) {
          errors.push(`${node.name}的姓名不能为空`);
        }
        if (node.requiredFields.age) {
          errors.push(`${node.name}的年龄不能为空`);
        }
      });
      if (errors.length > 0) {
        nameInputs.forEach((input) => {
          input.innerText = '';
        });
        ageInputs.forEach((input) => {
          input.innerText = '';
        });
        errors.forEach((error) => {
          const errorNode = document.createElement('div');
          errorNode.innerText = error;
          if (error.includes('姓名')) {
            nameInputs.forEach((input) => {
              input.parentNode.appendChild(errorNode.cloneNode(true));
            });
          } else if (error.includes('年龄')) {
            ageInputs.forEach((input) => {
              input.parentNode.appendChild(errorNode.cloneNode(true));
            });
          }
        });
        return Promise.reject('表单校验失败');
      } else {
        nameInputs.forEach((input) => {
          input.innerText = '';
        });
        ageInputs.forEach((input) => {
          input.innerText = '';
        });
        return Promise.resolve();
      }
    },
    submitForm() {
      this.$refs.form.validate().then(() => {
        this.validateRequiredFields().then(() => {
          console.log('表单校验成功');
        }).catch((error) => {
          console.error(error);
        });
      }).catch((error) => {
        console.error(error);
      });
    },
  },
};
</script>
``